20 ABSTRACTS OF CHEMICAL PAPERS. Mineralogic a1 C h ernis try. Absolute Hardness of Minerals. By F. PFAFF (Zeit. R ~ y s t . Min., 10, 528--531).-The author has made a series of experiments to determine the absolute hardness of minerals. An accurate chisel- shaped diamond cutter was passed with constant pressure in the same direction 100 or 1000 times over the face of the crystal, and the volume thus removed estimated by weighing the crystal before and after the experiment. A detailed description is given cf the instru- ment employed. Assuming that the hardness of two crystal planes is in inverse proportion to the volume of material removed, with t,he same load and the same number of passings to and fro of the diamond Over an equal area, the hardness of minerals can then be expressed numerically, a given substance (talc) being taken as unit.B. H. B.MiNERALOOICAL CHEMISTRY. 21 The Gold Beds of Mount Morgan, Queensland. By R. L. JACK (DingZ. polyt. J., 258, 45).--These beds are situated about 35 kilos. south-south-west of Rockhampton. The gold is distributed in hematite ironstone and in siliceous sinter. D. B. Copaline from Hiitteldorf, near Vienna. By G. Swam (Zeit. Kryst. illin., 10, 427).-In the slate of the Vienna sandstone, a fossil resin occurs in sharply angular fragments, or in sniall grains of 8 mm. diameter. Its colour varies between light greenish-yellow and brown. It is transparent to translucent. Several grains exhibit distinct fluorescence. It is brittle, fuses at 160 to 165" to a clear liquid.; at 360" it becomes brownish-black, bard, with metallic lustre, .and at a red heat it burns leaving no residue.B. H. B. Its density is less than 1.1. Pseudomorphs. By E. DOLL (Zeit. Rryst. Miw., 10, 423).-The anthor describes pseudomorphs of iron pyrites after copper pyrites, from Kapnik, and pseudomorphs of tetrahedri te after copper pyrites, from FelsobLnya. In the pseudomorphs from Kapnik and Felsiibinya described, and in the pseudomorphs of iron :pyrites after copper pyrites from Musen, numerous spherical cavities were o bserxed, around which the iron pyrites is grouped. This the author regards as a characteristic struc- ture for many pseudomorphs. Galena with Octahedral Cleavage from Wermland. By H. SJ~GREN (Zeit. K r y s t . Min., 10, 507--508).-1a a specimen of galens from Nordmarks mines in Dr.Lundstrom's collection, the usual cubical cleavage is not developed. On breaking up the specimen irregular fragments are formed of a distinctly octahedral character. The ordinary cubical cleavage is developed after two hours' heating at 200"; at 250" much more rapidly; and at 300" with still greater facility. Analysis gare the following results :- Pb. Bi. Ag. Pe. 8. Total. 85.67 0.76 0.05 0.39 13-59 100-46 B. H. B. The author is of opinion that the percentage of bismuth sulphide, which was also observed in the galena of Habach, may be the cause of the octahedral cleavage of galena. The galena, with octahedral cleavage, from Mt. Blanc, described by A. Brun (Abstr., 1883, 428), also gave on analysis 1 per cent. of bismuth sulphide. B. H.B. Tetrahedrite from the Alaska Vein, Colorado. By T. LIWEH (Zeit. Kryst. Min., 10, 488-489) .-The author has examined crystals of the new mineral from the Alaska vein, S.W. Colorado, described by Konig under the name of alaskite (Zeit. K r y s t . Min., 4, 42), in order t o prove crystallographically whether the mineral really belongs to the isomorphous rhombic group of copper-bismuth glance, lead-arsenic glance, &c. The measurements, however, showed the crystals to belong to the regular system; the mineral being evidently22 ABSTRACTS OF CHEMICAL PAPERS. tetrahedrite. A qualitative analysis showed the presence of S, Bi, Sb, Pb, Ag, Cu, Zn, the elements given by Konig in his analpis of 0 alaskite. The following forms were observed on the crystals : + %, 202 404 30 0 2 2 ' , + L , - 2 2' B.H. B. - 202 + -,03003,m0, -- - Microscopic Character of Variegated Copper Ore from New Mexico. By H. BAUMHAUER (Zeit. Kryst. Min., 10, 447-450) .-The author has examined, under the microscope, a specimen of bornite from Chloride, in New Mexico. He found that t,he compact bornite was of a crystalline character, with inclusions of copper glance. On treating these inclusions with concentrated nitric acid, it was seen that they consisted of a number of separate crystals, irregularly grouped together. I n addition to copper glance, a second mineral was observed here and there in the inclusions. This might possibly be galena. Small patches of copper pyrites also occasionally occur in the inclusions. In several places, the ore incloses small distinctly developed crystals of quartz.B. H. B. Antimonite from Czerwenitza. By H. v. FOUT~LOX (Zeit. Kryst, Min., 10, 429).-Antimonite occurs in the red trachytic mother-rock of the opals, in the form of hemispherical radiated aggregates, 1 cm. in diameter. These are frequently covered with hyalite. Several of the hemispherical aggregates of antimonite consist exclusively of an ti- monite fibres ; others, however, are found on microscopic examinatioii to consist of antimonite with interstratified hyalit'e, which the author regards as pseudomorphs after antimonite. Similar pseudomorphs are found a t the Josephis adit, in Klausenthal, near Eperies. B. H. B. Selenides from the Andes. By F. HEUSLER and H. KLIXGER (Ber., 18, 2556--2561).-Analysis of zorgite containing a con- siderable quantity of silver.The substances are not homogeneons ; analysis of the different parts gave- 45 Cu. Pb. Co. Bi. Se. Total. I . . . . 19.20 12.43 35.70 traces - 32.77 100.09 11.. , . 27-49 25-40 17.10 0.39 - 25.54 99-92 L--d 111.. .. 15.87 36.15 1.73 46.25 100.00 I V . . . . 19.16 35.77 3.45 41-62 100*00 I and I1 clear bluish-green substance of silvery lustre. I agrees with the formula Ag2Se,2PbSe,2CuSe. I11 and lV, darker samples of bluish lead colour, are essentially selenides of silver and copper (comp. Pisani, Abstr., 1880, 440). A. J. G. Refractive Indices of Fluorspar. By E. SARASTN (Zeit. K r y s t . Min., 10, 523- 524).-The author has determined the refractive indices of a fluorspar prism, with a refraction angle of 60" 4' 55".A table of the results is given for the spectrum lines, A, a, R, C, D, F, h,MISERALOGICAL CHEMISTRY. 23 H, (Cd) 9, 10, 11, 12, 17, 18, 23, 24, 25, 26, (Zn) 27, 28, 2% (A]) 3% 31, 32. B. H. B. Optical Properties and the Micro-structure of Corundrum. By A. v. LASAULX (Zeit. R ~ y s t . Min., 10, 346--365).-Corundum is without doubt an optically uniaxial mineral crystallising in the hex- agonal system. Disturbances in the regular optical behaviour depend on the nature of the growth and the structure of the corundum cryst'al. The crystals occurring in volcanic rocks appear, as a rule, to have a more uniform constitution and a more regular optical beha- vionr than those found in the older crystalline rocks. The optical disturbances appear tliroughout to be connected with the more or less distinctly developed sbructural faces parallel to R, wP2, and OR.The concentric structure in the direction of one or other of these planes determines the cleavage, which is developed in the direction of R alone, or R and OR, or mP2 and OR, or all bhree planes a t the same time, more or less perfectly. The cleavage is not dependent on the twin lamellae present, but on the other hand the latter are dependent on the presence of the structural planes which determine the cleavage. But both appear simult,aneously almost always. In this- case, struc- tural and twin planes are identical. In the direction of mP2, the plane of symmetry, a twin formation is not possible ; in bhe direction of OR it is entirely unknown, The optical disturbances hi the zone lamell= bounded by the structural planes are, however, of two kinds : -1.Optical disturbance is effected by tension in the zones of the crystal. 2. It occurs in consequence of interpolated twin lamell=. Lastly, optical disturbances also occur in corundum crystals, in con- sequence of processes of alteration, producing granular, laminated, or fibrous products in the interior of the crystals. Jn this case, how- ever, a regular interference figure is not exhibited. B. H. B. Corundum in Graphite. By H. WICHMANN (Zed. Kryst. Min., 10, 425).-On the surface of the graphite of Muhldorf, near spit^, in Lower Austria, small crystals of corundum occur. The crystals attain a thickness of 0.5-6 mm., and a length of 7-25 m u . They are of a red to blue colour, rarely grey, but always clouded with inclu- sions.The translucent crystals prove to be biaxial, with a rather large axial angle. Gahnite and Epidote from Rowe, Massachusetts. By A. G. DANA (Zeit. K7yst. Xi)! ., 10, 490 -492).-With iron pyrites, copper pyrites, and quartz, the author found at Davis' mine, Rowe, frag- ments of gahnite, which on analysis gave the following results :- Al,O,. Fe,O,. FeO. MnO. MgO. ZnO. Si02. Total. Sp. gr. 54 83 3.00 3.37 iirace 1.93 36.92 0.53 100.58 4-53 The following minerals also occur associated with the gahnite :- Ilmenite, apatite, rutile, sphalerite, garnet, calcite, green crystals of ;t triclinic felspar, and epidote. The epidote occurs in short prisms, opaque, and of a greenish-grey colour. Analysis gave the following results : - B.11. B.24 ABSTRACTS OF CHEMICAL PAPERS. SiO,. A1,03. Fe20,. MnO. MgO. CaO. Alkalis. H20. Residue. Total. 38.20 24.62 12-20 0.57 0.13 21-59 0.37 2.16 0.35 100.19 Goethite from Pitkaranta, in Finland. By M. WEIBULL (Zeit. Kryst. illin., IQ, 511-$12).-The author describes specimens of quartz aiid fluorspar w.ith..cavities lined with rock crystal and haematite, on which needles land radiated, aggregates of goethite were crystallised out. An analysis of the goethite gave 89-65 per cent. of ferric oxide, and 10.50 per cent. of water. The mineral is therefore a very pure goetliite. B. H. B. Zircon in Sbsratified Rocks. By F. SANDBERGER (Zeit. Kryst. $!in., 10, 405).-The author has observed transparent crystals of ~ r c o n in the granite of Schapbach, in the Black Forest, of Windeck, near Weinheirn, of Heidelberg, Ilmenau, of the Luisenburg, near Wunsiedel, Nabburg and Worth, near Regensburg.The crystals exhibit exclusively the combination mPm. Transparent zircons are also found in gneiss and mica-diorites, and in the porphyry of the Wagenberg, near Weinheirn, Microscopically small zircons of the same form are widely distributed in the sedimentary rocks, the mate- rial of which is mainly derived from the older rocks ; for example, iii the variegated sandstones of the Black Forest and Spessart, in car- boniferous sandstone, in the Upper Keuper sandstone, and in the sands of the Valley of the Maine. B. H. B. B. H. B. Boracite. By H. BAUMHAUER (Zeit. K ~ y s t . 3&, 10, 451-457).- The author brings forward further arguments to prove that boracite at; the ordinary temperature, in the state in which it is met with in nature, does not crystallise in the regular, but in the rhombic system.Uranothallite. By A . BREZINA (Zeit. Kryst. &!in., 10, 425-426). -Crystals of uranothallite recently obtained at Joachimsthal, gave, for the rhombic crystals, the axial ratio a : b : c = 0.954 : 1 : 0.783. The analysis gave the following results :- uop cop. CaO. FeO. HzO. Total. B. H. B. 35.45 23-13 16.28 2-48 22.44 99.78 corresponding with the formula 2CaC03 + UC20, + 10H20. B. H. B. Occurrence of Hornstone and Barytes in the Porphyry District of Teplitz. By G. LAUBE (Zeit. K~yst. A&., 10, 421).- I n a description of. a crystal of barytes from Teplitz, in Bohemia (Zeit. Kryst. Mi72., 9, 2 2 l ) , Becke stated that the crystal was deposited from the'Teplitz mineral water, which, according to the analyses of Sonnenschein, contains no barytes.This statement the author corrects by showing that barytes occurs in mineral spring fissures only where they traverse the Cenomanian hornstone-conglomerate occurring in the neighbourhood of Teplit z. From these fissures honey-yellow crystals of barytes have been long known. The Teplitz springs, however, do not contain barium. Only in the Neubad spring haveMISERALOGICAL CHEMIST kT. 25 traces of ba,rium been found. conglomerate conhaining baryt)es. This spring passes through hornstone- B. H. B. Halotrichite and Epsomite from the Falu Mine. By &I. WEIBULL (Zeit. Kryst. Min., 10, 512).-In two portions of the Falu mine, where the degree of moisture is low, and the temperature relatively high, sponge-like ma.sses occur of a recent mineral, which appears to be a mixture of epsowite and hnlotrichite.The sp. gr. of the mixtnre is 1.77. The analysis gave results corresponding with the formula- 2(MgS04 + 7%0) + (FeZnCa)(AlFe),(SO& -t 22H20. B. H. B. Turquoise from Nischapur in Persia. By E. TIETZE (Zeit. E r y s t . iklin., 10, 428) .--The mother-rock of the turquoise of Nischapur is, contrary to all former descriptions, a porphyritic trachyte. I n this, and in a breccia formed of angular fragments of the frachyte, the turquoise occurs in veins, 2 to 6 mm. thick, or in irregular patches. In the trachyte, pseudomorphs of turquoise after orthoclase occur. Turquoise is also found in shapeless fragments in the alluvium in the neighbourhood of the trachyte rocks.Berzeliite. By L. J. IGELSTROM (Zeit. Kryst. ikfin., 10, 516- 517).-The author notes the discovery of berzeliite, hitherto found only at Lingban, a t the Moss mine in Wermland. An analysis gave the following results :- B. H. B. As,O,. CaO . MgO. Mn, Pb and C1. 57.80 25.25 16.95 traces This corresponds with Dana's formula for berzeliite- (CaMgRfn) 10A~6025. B. H. B. Xanthoarsenite, a New Mineral from Oerebro. By L. J. IGELSTROM ( X e i t . Kryst. Min., 10, 518-519).-l'he new mineral occurs at a small iron mine 6 miles east of Grythytta. Its colour is sulphur-yellow to orange. In thin splinters, it is translucent. Before the blowpipe, it melts to a black glass, giving a strong odour of arsenic.As,O,. MnO. FeO. MgO. CaO. H,O. 33.26 43-60 3.11 6.08 1-93 12.02 Analrsis gave the following results :- B. H. B. Manganostibite, a New Mineral from Wermland. Ey L. J. TGELSTROM (Zeit. Kryst. Min., 10, 519).-This mineral occurs a t the Moss mine, in small, black, rhombic crystals. An analysis of 0.54 gram gave the following results :- Sba06. AszO,. MnO. FeO. CaO. MgO. Total." 24.09 7-44! 55.77 5-00 3.62 3.00 99-92 * The figures given only add up t o 98.92. B. H. B.26 ABSTRACTS OF CHEMlCAL PAPERS. Vanadates and Silver Iodide from New Mexico. By F. A. GemH and G. v. RATH (Zeit. Krysf. Min., 10, 458-474).-Quite recently new workings a t the Sierra Grande Mine, Lake Valley, Donna Anna Co., New Mexico, have yielded a number of highly interesting and rare minerals, which have been examined chemically by F.A. Genth, and crystallographically by G. v. Rath. Vanadinite, from the Sierra Bella Mine, Lake Valley, gave the following results on analysis :- C1. P,05. V,05. As205. PbO. Total.* Sp. gr. I.. . . 2.39 0-57 17-37 0.24 79.43 100.00 - 11.. . . 2.49 0.39 17.44 1.33 78.31 100.26 6.862 I1 is the analysis of vanadinite from the Sierra Grande. This corresponds with the formula Pb,Cl[ (VAsPb)0,I3 ; whilst analysis I gives a small excess of lead, probably present as cerussite. Lead Ai*sen,io-vanadate-End 1ichite.-An analysis of a supposed vanadinite from the Sierra Grande gave the following results :- SiO,. Fe203. CaO. C1. As205. V20+ PbO. C02,H,0. Total. 76-44 0.99 0.30 0.44 2.16 1-60 15.94 C2.131 100.00 The mineral has thus the composition of equal mols.of mimetite and vanadinite : Pb5C1(AsOJ3 + Pb5C1( VO,),. This mineral the authors believe to be new, and propose for it the name of endlichite, after the director of the Lake Valley mines. Desc1oizite.-Very fine red and brown crystals have recently been found a t the Sierra Grande. The mean results of three analjses of t'he red (I), and of three analyses of the black variety (11) gave the following results :- PbO. CuO. ZnO. MnO. FeO. Ae205. V,05. I1 , . . . 36-36 0.87 13.91 2.74 0.30 0.50 21.35 P205. H,O. Total. Sp. gr. I .... - 2.37 99 49 6.106 I1 . . . . 0.04 3.39 99.46 5.848 After subtracting the impurities shown by the black descloizite, itas analysis agrees vary well with that of the pure red, the composition being expressed by the following formula :- Pb,(HO) (V,As,P)O, + (Zn,Mn,Cu,Fe)z(HO)(V,As,P)O,.I . . . . 56-12 1.10 17*&1 0.49 0.15 0.20 21.65 No indunium is present in the vanadates of Lake Valley. On the ne_w descloizite crystals, thefollowi~ig form? were observed:- P, 2P2, gP3, $Pm, ZPm, COP, mP3, cnP03, m P q OP, with the rhombic axial ratio, a : b : c = 0.6367 : 1 : 0.8046. Silver iodide.-Pure silver iodide is frequently found accompanying the vanadates of the Sierra Grande. It occurs with calcite and red descloizite in yellow, indistinct crystals and crystalline masses ; and with vanadinite and black descloizite i n very small, indistinct, rounded crystals. B. H. B. * The figures giren only add 1113 t o 93.96.BIINERALOGI(I1AL CHEMISTRY.27 Minerals of the Pegmatite Vein at Moss. By W. C. BROGGER (Zeit. Z(ryst. Min., 10,494-496).--The author gives a long list of the minerals occurring in the pegmatite vein at Moss, the remarks on the new mineral atlneyodite being of special interest. This mineral is black with metallic to resinous semi-metallic lustre. H. = 6 ; sp. gr. 5.7. Analysis gave the following results :- Nb,O,. SnO?. SiO,. Zr02 UO,. Tho,. Ce oxides. Y oxides. PbO. 48.13 0.16 2.51 1-97 16.28 2.37 2.36 7.10 2.40 FeO. MnO. CaO. MgO. K,O. NasO. Also,. H20. Total. 3.38 0.20 3.35 0.15 0.16 0.32 0.28 8.19 99.51 corresponding with the foimula 2R,NbL0,(+ 5H20 + +SiO,>. The mineral, therefore, resembles samarskite, from which it differs crystallographically. The axial ratio is rhombici a : b, : c = 0.40369 : 1 : 0;3610,3.The fojms observed yere,_mPm, mPm, OP, WP, mP3, mP5,2Pm7 $Pm, Pm, P, 2P2, 2P2, 3P3,2P, B. H. B. Quartz from Burke, North Carolina. By G. v. RATH (Zeit. Kryst. ZCIin., 10, 475-487) .-A description of peculiar crystals from this locality. Opal from Nagasaki, Japan. By H. SJOGREN (Zeit. I(ryst. Min., 10, 508).-The mineral is of a yellowish-brown to chesnut-brown colour, and possesses the usual characteristics of opal. Under the microscope, 110 trace of organic structure could be detect'ed. Analyses of material dried a t 133" (I), and of undried material (11), gave the following results :- H,O. SiOs. Fe203. A1,03. MgO. Total. I . . . . 3.59 88-87 5.26 1-84 0.32 99.88 I1 . . .. 8-87 84.36 4.99 1.74 0.30 100.26 The latter analysis corresponds with the composition of menilite, H2Si30s.B. H. B. Change in Colour in Felspar due to the Action of Light. By E. ERDMANN (Zeit. K ~ y s t . Min., 10, 493).-From the pegmatite veins of the Ammeberg zinc mine, the author collected specimens of amazonite, with which he made the following experiments :-A large fragment was broken into three parts, 5 to 10 cm. long, the fresh fracture showing a pale greenish-grey colour. Of these pieces, one was packed up in black paper and kept in a dark place; the two others were exposed to the action of sunlight, one having a strip of black paper 10 mm. wide pasted on and varnished, the other having a strip of the same width varnished to exclude air and moisture, but not light. The two specimens were exposed to the action of the sun, air, and rain for 74 days.It was then found that the original pale28 -4BSTRACTS OF CHEMICAL PAPERS. green colour had become a deep emerald-green ; the portion protected by the black paper and the specimen kept in the dark room having remained unaltered. The layer of varnish had cracked, so that it could not be decided whether the change was due to air and moisture, or to light alone. A second experiment was then made. A piece of the unaltered felspar was broken up, and small pieces placed in five tubes of different colours (black, blue, yellow, pale emerald-green, and colourless). The open ends of the tubes were then sealed, without heating the felspar, and the tubes exposed to the action of light for 10 months. On opening the tubes, the felspar in the colourless tube was found to be of a deep emerald-green colour; the felspar in the green tube was less altered, still less in the yellow, and inappreciably in the blue, whilst in the black tube it was quite unaltered.The change in colour is due, therefore, to the action of light alone. B. H. B. Apophyllite from Wermland. By L. J. IGELSTROM (Zeit. Kryst. Min., 10, 517).-At the Nordmarks mines the author found, in addition to the ordinary apophyllite in crystals, concentrically radiated globnlar masses of the same mineral, 2 to 3 em. in diameter. An incomplete analysis gave the following results :- Si02. CaO. MgO. K20,Naz0,B’. H,O. Total. 52.00 23.20 1.30 7.10 16.40 100.00 B. H. B. Chemical Composition of the Amphiboles. By F. BERWERTH (Zeit. K~ysf. Mim., 10, 406-409).-1.li.emoZife.--The mean of two analyses of tremolite from St. Gottharcl gave the following results :- SiO,. d1,0,. FeO. CaO. MgO. H,O. Total. Sp. gr. 58.40 0.56 0.26 13.63 24.82 1.85 9952 3-02 Making allowance for the talc mixed with the specimen analysed, the analysis corresponds with the formula ( CaSi03) (MgSi03) (H2Si03). 2. Actindite.-The author gives the formula for pure actinolite as I 5CaSi03 9MgSi03 2HzSi03 3. Arfvedsonite, from the Nuriasornausak Mine in Greenland, gave on analysis the following results :- Si02. A1,0,. Fe,O,. FeO. CaO. K20. Na20. HzO. Total. Sp. gr. 47-08 1.44 1.70 35.65 2.32 2.88 7.14 2.08 10029 3.45 The author assumes that muscovite is mixed with the mineral analysed, and that the formula for pure mfvedsonite is 13FeSi0, CaSiO, 4Na2 Si03 2H2SiO3MINERALOGICAL CHEMISTRY.29 4. Alunzina-hornbleizd~, from Vesuvius, gave the following analj tical results :- SiOP A120,. Fe203. FeO. CaO. MgO. KJ3. 39-80 14-28 2-56 19.02 10.73 9-10 2.85 Ka20. HaO. Total. Sp. gr. 1.79 1-42 101.55 3.29 The author is of opinion that, as the amount of mica mixed with the hornblende is very small, the hornblende crystals were built up of calcium silicate and meroxene moleciiles, and assumes that at first the tendency to form meroxene predominated, but that the regular develop- ment of the merosene was disturbed by the calcium silicate coming into play. By the calcium silicate and memxene crystallising toge- ther, a hornblende crystal resulted as terminal product. 5. Alumina- hornblende (Pargasite), from the granular limestone of Pargas, had the following composition :- F.Si02. Al,03. PeO. CaO. MgO. K20. 1.66 42.97 16.42 1.32 14.99 20.14 2-85 RTa30. H20. Total. SP. gr. 1-53 0.87 102.75 3.11 Subtracting the 35.91 per cent. of mechanically mixed phlogopite, the formula, for the pure pargasite is I 8Si3A1,0,2 9SiCa204 7 Si hl g204 SiHp04 6. Glaucophune, from Zermatt, gave the following results on SiO> A1903. FeO. CaO. MgO. Na,O. H,O. Total. Sp. gr. 58.76 12.99 5.84 2.10 14.01 6.45 2.54 102.69 3 04 analysis :- The quantity of paragonite admixed could not be determined. Alterations of the Garnets in the Amphibole Schists of the Tyrol. By A. CATHREIN (Zeit. K ~ y s t . Min., 10, 433--446).-1n rocks from the Stamser Alps, the author has observed garnets altered into scspolite, epidote, oligoclase, hornblende, saussurite, and chlorite.B. H. B. B. H. B. Vesuvian Humite, Chondrodite from Nyakopparberg, and Humite from Ladugrufvan. By F. C. v. WIHGARD (Zeit. Anal. Chem., 24, 344-356).-The above minerals (with the exception of the Ladup-ufvan humite) showed no trace of alteration to serpentine. The fluorine was determined by the direct method of Fresenius, except in the case of the Vesuvian humite of type 11, and that from Ladu- grufvan, where the small quantity of material would only allow of the30 ABSTRACTS OF CHEMICAL PAPERS. use of Berzelius' process. After drying a t 110", the minerals still contained hydrogen. This was determined by igniting with lead oxide and weighing the expelled water. The following are the analytical results :- I.Vesuvian humite, type I, or hurnite of Descloiseaux. 11. Vesuvian humite, type 11, or chondrodite of Descloiseanx. 111. Vesuvian humite, type 111, or clinohnmite of Descloiseanx. IV. Chondrodite from Nyakopparberg : a, pale wine-yellow ; b, Pale win e-y ellow. Pale brownish-yellow or greyish-brown. honey-y ello w. V. Humite, type I, from Lndugrufvan. SiO,. MgO. FeO. Fe,03. MgF2. HzO. Total. 1 . . , . . . 35-49 49.47 4.32 - 9.20 1-45 99.93 11 .. . . . . 3.3'49 52.87 3.80 - 8.39 1-37' 9992 111 . . . . . . 33.40 45.65 9.63 0.82 9.25 1.41 100.16 a. 33.90 47.65 7.76 0.11 9.10 1.31 99.83 b. 31.56 37.54 18.67 2.01 9.10 1.31 100.19 V . . . . . . 35.26 50.51 3.51 - 7.70 3.07 100*05 The completely unaltered condition of the specimens, and the fact) that the water was not expelled below a red heat, negative the sup- position of v.Rath that the deficiency in the older analyses was due to water of hydration, and require the hydrogen to be regarded as existing in the form of hydroxyl, replacing fluorine isomorphouslg. The fluorine determinations (of which the above numbers are the averages deduced from numerous concordant results) do not exhibit the wide variations found by other analysts, and, in fact, with the exception of 11, in which i t is assumed that the fluorine is below the truth, of IVb, which is rejected, and of the excess of water inV, due to an obvious partial alteration, all these numbers (after calculating the iron as magnesium) lead to the identical formula IV ... { for all the three types. M. J.S. Isomorphous Silicates. By C. RAMMELSBERG (Chew,. Centr., 1885, 687--688).-The author has endeavoured, by a series of experi- ments, to add to the knowledge of the chemical nature of the members of the scapolite group. All the members of this group are perfectly isomorphous. They are called by various names, but quali- tatively their composition is the same ; they are silicates of alumina, lime, and soda. Only in one member, humboldtilite, do iron and magnesia occur to a considerable extent. There is no soda-free scapolite known, corresponding with anorthite, nor a lime-free scapolite, corre- sponding with albite, which, like the above-mentioned minerals of the felspar gronp, could be regarded as terminal members of the series. The composition of the various members of the group, however, is very different; the proportion of acid amounts to 40 to 60 per cent., that of lime varies from 24 to 4, whilst the amount ofMIXERALOGICAL CHEMISTRY.31 soda amounts to 2 to 10 per cent. With the variations in the atomic proportion of Na : Ca : A1 : Si, it appears desirable to assume Ca = 2R, A1 = 6R, and to calculate the ratio R : Si. In this way the author found that the scapolite group includes: (A) semisilicates ; (B) com- binations of normal and semi-silicates ; (C) normal silicates ; and (D) combinations of normal and quadri-silicates. He concludes that in the scapolite group only the simplest silicates occur, namely :- Normal. . . . . , . . . . Semisilicates . . . . Quadrisilicates . . . and combinations of any two of them.I n group B, which includes the majority of cases, combinations of 1 and 6 mols.,of 1 and 3 mols., of Z and 1 mol., and of 4 and 1 mol. of normal and semi-silicate, are found. The combination of normal and quadri-silicate (group D) consists of 3 and 1 mol. B. H. B. Mineralogical Notes from Bohemia. By R. RAFFELT (Zeit. Kryst. Min., 10, 42l).-In fissures and cavities in the basalt of the E ulenberg near Leitmeritz, the author found analcime, chabasite, phillipsite, and thomsonite, with aragonite and calcite. The analcime forms thin, crystalline crusts exhibiting the form 202. Chabasite occurs in yellow, twin crystals ; phillipsite also occnrs in twin crystals. On the latter are frequently planted crystals of thornsonite, with the following composition :- Si02.Al,O,. CaO. Na,O. HzO. Total. 38.44 31.48 13.60 3.53 12.93 99.98 N%SiO, ; CaSiOs ; AISi,O,. Na,Si04 ; Ca2Si04 ; A12Si3012. Na,Si,O, ; CaSi20, ; AlS&O,,, B. H. B. Empholite, a New Mineral from Horrsjoberg in Wermland. By L. J. IGELSTROM (Zeit. Kryst. Min., 10, 521).--'l'his new mineral forms white or yellowish, translucent crystals, and radiated aggregates in damourite and pyrophyllite in gneiss. The minsral crysta_llises in the rhombic system with the planes mP, d 0 3 , mP2, and mP3. The plane of the optic axes is parallel to the brachypinacoid ; the acute bisectrix is parallel to the brachydiagonal, positive ; the obtuse bisectrix is parallel to the vertical axis. In appearance the mineral resembles diaspore ; H. = 6. Analysis gave the following results :- SiO,.A1203. MgO,CaO,FeO. H,O. Total. 51-70 31.52 4-60 12.18 100.00 (Compare Abstr., 1885, 31.) By L. J. IGELSTROM (Zeit. Kryst. Min., 10, 522).- An analysis of the mineral discovered by the author in 1860, and named persbergite, shows it to be a mineral resembling falunite. The analytical results were as follows :- B. H. B. Persbergite. Si02. Al,03(Fe,03). Mg0,CaO. H20. Total. 41-20 2 7-50 18*LO 13.08 1UO.00 B. H. B.32 ABSTRACTS OF CHERlICAL PAPERS. Minerals from the Mica Diorite of Christianberg, Bohemia. By G. STARKL (Zeit. IZryst. Him, 10, 427).-The minerals examined were biotite, hornblende, plagioclase, and apatite. The three first minerals on analysis gave the following results :- Si02. Al,03. Fez03. Cr203. FeO. CaO. MgO. K20. I.. 39.53 13.45 8.06 0.14 4.99 3.38 22.52 4.13 111..65-54 21.74 trace - - 2.14 trace 3.32 N8.20. H2O. SP. gr. I .......... 1.22 1.49 2.81 I1 .......... - 1.04 2.9% I11 .......... 7.75 0.35 2.57 11.. 5.3.8:3 3.78 3.50 0.08 6-83 10.32 19.49 - Corresponding with the formula+- I. Biot,ite. ..... 2[ (HzNazK2)zSi04] + 11 [ ( FeCaMg),Si04] 11. Hornblende . 15(RSiO,) + l(R;"Si309). 111. Plagioclase . . 2(&~Al~si~o,~) + 6(Na2A1,Si6Ol6) + 1( Ca2A14Si40,6). Chemical Constitution of Staurolite. By W. FRIEDL (Zeit. K r y s t . Mi%., 10, 366-373).-Analyses of staurolite (1) from St. Gottliard and (11) from Tramnitzberg, in Moravia, gave the following + 3[ (~2FezCr2)zSi3O,z]. B. H. B. results :- Si02. A1,03. Fe203. FeO. MgO. H20. Total. I . . 28.1.5 52.17 1.70 13.84 2.54 1-63 100.03 I1 . . 28.19 52.15 1.59 14.12 2.42 1.59 100.06 Both of these analyses correspond with the formula H4( FeMg) 6( AlFe) 24SiiiOs6, O r (FeMg)6A&(AIO) m( OH),( SiO,) 11.This formula, based on analyses of rna'terial proved to be pure by microscopical examination, differs from Rammelsberg's formula for staurolite by Q mol. SiO,. And the ferric oxide, passed over by Kammelsberg, is taken into account in the new formula. An estimate of the value of the two formulst: may be formed from the foIlowing comparison of the actual and calculated results :- I, New staurolit e formula, B4 (A1 ,-$sFe) 24 (iB'e, M g) Si11066. Si02. Al,03. FezO3. FeO. MgO. HzO. Total. Calculated . . 28.38 51.87 1.68 13.93 2.58 1.55 99-99 Found ...... 28.17 52.17 1.65 13.98 2.48 1-61 100.06 11. Old staurolite formula (according t o Rammelsberg, taking into account the percentage of ferric oxide discovered by the author), Hz(~Fe,~~g)~(Al,-a,Fe) 1~Si~034.SiO,. Al,03. Fe203. PeO. MgO. H20. Total. Calculated.. 30.18 50.58 1.64 13 58 2-51 1.51 1OU.t)O Found.. .... 29.46 52.29 - 13.42 2.29 1.60 99-061lINERALOGlCXL CHEMISTRY. 33 The percentage of aluniina found by Rammelsberg exceeds the calculated amount by 1.71, whilst the silica percentage is 0-72 less than the calculated. On comparing his analysis with that of the microscopically tested material, it is evident the staurolite he employed contained some quartz. It may consequently be assumed that staurolite has the formula of a basic silicate :- (MgFe)&,( AIO),( OH),( siod 11 = &(Mg,Fe)6( A1Fe)24Si,,0,6, whichrepresents the simple oxygen ratio of 2 : 1.Pycnophyllite from Aspacg. By G. STARKL (Zeit. Krpf. Min., 10, 427--428).-The author gives the name of pycnophyllite to a compact, finely laminated substance, which fills the fissures of a talc-mica schist, south-east of Aspang. The mineral is of a preen colour, is greasy to the touch, adheres to the tongue, has a resinous lustre, H. = 2, sp. gr. 2.7!16, is easily split up parallel to one plane. Thin leaves are translucent, biaxial, negative. In composition the mineral mast resembles hygrophilite o r pini te. The analjses of specimens from two localities in the neighbourhood of Aspang gave the following results :- SiO,. d1,03. Fe&. FeO. CaO. MgQ. K20. Na20. H20. 48.88 -29.37 2.38 0.51 1.24 2.67 6.51 3.34 4.62 50.09 26.47 3.66 - 0.44 3.93 10.77 4.61 B.EI. B. Igelstromite from Delarne. By M. WEIBULL (Zeit. Kryst. Mi%., 10, 511).-This mineral, formerly desc~ibed by the author (Abstr., 1884, 409), from the Silferberg mines, has been recently found four miles further to the south-west in the Hillangs mines. The deposit cousists of magnetite with mangnnocalcite, silicates rich in man- ganese (igelstromit e, actinolite, and gnrnet), arsenical pyrites, and magnetic pyrites. An analysis of the igelstrornite gave the following resnlts :- B. H. B. - SiO?. FeO. MnO. MgO. CsC03. Total. 28-76 48.59 18.57 1.93 2.25 100.15 corresponding with the formula- 2(FeMg)2Si04 + (MnMg),Si04. B. H. R. Minerals of Vester-Silfberg. By M. WEIBIJLT, (Zeit. TG-yst. Mi?? , 10, 512-515).-The author gives a detailed description of a numb, L' of minerals occurring a t Vester-Silfberg.Manganocalcite from the Stollberg gave on analysis the following results :- CaO. MnO. FeO. MgO. C02. Insoluble. Sp. gr. 46.22 6.98 3.01 0.22 (42.86) 0.71 2.804 WmeRponding with the formula 6Catc03 + (MnFe)C03. The mineral VOL. L. d34 ABSTRACTS OF CHEMlCAL PAPERS. thus approximates closely to Breithaupt's so-called spartaite. An analysis of manganese-hisingerite, an alteration-product of igel- stromite, gave the following results : - Si02. Fe,03. Mn,03. Al,03. MgO. CaO. H20. Total. Sp. gr. 37-09 34.34 15.50 1.39 2.62 1.92 7.81 100.67 2.469 An analysis of silfbergite gaye- Si02. FeO. MnO. MgO. CaO. A1203. Ignition. Total. 49.50 30.69 8-24 8.10 2.02 0.69 0.40 99.64 corresponding wit,h the formula (FeMnMgCa)Si03.The author further mentions the occurrence of magnetite, igelstriim- ite, iron-rhodoni te, and manganese-hedenbergite (compa,re Abstr., 1884, 409). B. H. B. Manganese Minerals from Wermland. By L. J. IGELSTR~M (Zeit. Kryst. Min., 10, 519-521) .-The manganese minerals of the so-called steel ore mines of Giisborn in Wermland, axe manganese silicates, and are largely employed in steel making. The author has made several analyses of these silicates, the results being as follows :- R i 0 2 . MnO. FeO. CaO. MgO. &03. Fe,O,. Ignition. Total. 2.10 100*00 11. 47.00 31 20 10.60 5.70 2.50 - - 0.80 97.81 111. 38.63 13.00 - 19.80 - 8.20 21.90 - 101.53 I. Rhodonite ; 11. Rhodonite, with grains of magnetite; 111. A yellow manganese silicate gave the following analytical results :- I.42.37 40.63 6.80 8.10 - - - brownish and manganese garnet. Total insoluble SiO,. FeO. MnO. CaO. in acids. 38.35 14-05 29.52 10.52 92.46 Total soluble MnC03. FeC03. CaCO,. in acids. 3-70 2.01 1-36 7-07 B. H. B. Chemical Composition of Katapleite. By A. SJOGREX (Zeit. Kryst. M h . , 10, 509-510).-The mean of two new analyses of kata- plgite is as follows :- SiO,. ZrO2. FeO. CaO. Na20. H20. Total. 44-13 32.00 0.19 5.56 8.52 9-26 99.66 The author, therefore, concludes that the formula of kataplgite is (Na.J3aFe)Si03 + ZrSi20s + 2H,O. B. H. B. Two New Norwegian Minerals. By W. C. BR~GGER (Zeit. Kryst. Min., 10, 503-504).- I. Lausnite. Monosymmetrical. Axial ratio a : b : c = 1.0811 : 1 : 0.8153 ; B = 71" 24+', with the combination3IINERALOGICXL CHEMISTRY.35 mP, mP2, mPm, 0332~0, - P, - PWO. The optic axial plane is the plane of symmetry, the acute bisectrix forming with the vertical axis an angle of 20y. Cleavage perfect in the direction of the ortho- pinacoid. Colour chesnnt-brown to yellow. Slightly translucent. Analysis gave the following results :- 33.71 31.65 5.64 5.06 11-00 11.32 1-03 99.41 3.51 This very rare mineral was formerly regarded by the author its mosandrite, which it closely resembles. 2. Cuppe2enite.-A greenish-brown mineral i n thick prismatic crystals, translucent to semi-transparent. Hexagonal ; axial ratio u : c = 1 : 0.43010 ; combination, COP, P, 3P, OP. 550,. ZrO,. Fe203. MnO. CaO. Na,O. Ignition. Total. Sp. gr. Analysis gave the following results :- SiO,. B203.Y20,. (LaDi),03. Ce2@. Tho2. BaO. 14.16 (17.13) 52.55 2-97 1.23 0.79 8.15 CaO. Na,O. K20. HzO. Total. Fp. gr. 0.61 0.39 0.21 1.81 100~00 4.407 B. H. B. Barium Sulphate as a Cementing Material in Sandstone. By F. CLOWES (Clzem. News, 52, 194).--In cerhin New Red Sand- stone beds in the neighbourhood of Nottingham, known as Stapleford and Bramcote Hills, and the Hemlock St,one, the cementing material has been shown by the author to be crystalline barium sulphate. The Hemlock Stone is mushroom shaped, and whilst the- lower portion is calcareous sandstone, the upper portion is not, but contains bavium sulphate, to which fact most probably the stone owes its sha,pe. The barium sulphate occurs in some of the beds in streaks, patches, and large and small more o r less spherical masses ; the intervening ssnd being loose, weathered surfaces appear honey-combed or mammellated, and in one case yield pebble-like masses of sand held togwther by barium sulphate.D. A. L. Weathering of Sandstone. By J. STOKLASA (Landw. Versuchs-Xtaf., 1885,203-214).-The sandstone examined contained 41 per cent. of quartz, and had a sp. gr. of 2.3-2.5 at 17". The changes which this class of stoue undergoes may be thus classified : oxidation of the ferrous compounds (yellowing) ; partial solubion of carbonates ; loss of half the total calcium carbonate with relative increase of silicates and qiiartz; and final pulverisation of the mass. The analytical tables show clearly the conversion of insoluble into soluble compounds, especially in the case of the phosphates which rapidly become soluble in acetic and citric acids.E. W. P. Application of Thermochemistry to Geology. By DIEULAFAIT (Compt. rend., 101, 609-612, 644-64G, and 676--ti79).--The object of the author's investigations is to ascertain how far the main facts of geology can be explained by thermochernical laws, the inquiry being d 236 ABSTRACTS OF CHEMICAL PAPERS. limited in the present papers to the formation of minerals at the ordinary temperatures from subslances in aqueous solution. develops + 26.6 cal. From a consideration of the following reactions- 2Fe0 + 0 = Fe,O,, 2Mn0 + 0, = 2Mn02, 9 , + 21.4 9 , 2Fe0 + 2C0, = 2FeCO,, ,t + 10 0 9 ) 21In0 + 2C0, = 2MnCO3, ,, + 13.6 ,, it would follow that when oxygen and carbonic anhydride, both in ezcesc, come in contact with silicates or other minerals containing ferrous and manganous oxides, the latter will be converted into ferric oxide and manganese peroxide respectively, and no carbonates will be formed.If, however, the carbonic anhydride and oxygen come in contact with the minerals slowly and in quantity insufficient to completely trans- form both oxides, the oxygen will combine mainlv, if not entirely, with the ferrous oxide, and the carbonic anhydride, being unable to cmbine with the ferric oxide thus formed, will .unite with the manganous oxide in preference to uniting with the still un- altered ferrous oxide. The products will, therefore, be femic oxide, which is insoluble, and manganous carbonate, which is distinctly eoluble. If the two gases are dissolved in water percolating through primary rocks, the issuing water will contain manganous.carbonate in relatively much greater proportion than in the original rock, and it is easy to see that this explains the formation of manganese I minerals comparatively free fi-om iron, from rocks in which iron is present in considerable quan1,ity. Since the heat of formation of ferric oxide is so much greater than that of 'ferrous carbonate, it follows that the latter can only be formed in a reducing medium, and can only remain unchanged so long as it is protected from the action of oxygen. Naturtil ferrous carbonates may be divided into two groups : spathic 'iron, which is crgsta7listtd, and exists in the oldest rocks as well as in comparatively recent formations ; and lithoidal ferrous carbonate, which is confined t o the carhon7ferous horizon.The formations in whibh this lithoidal ferrous carbonate occurs, are of estuarine origin, and hence the ferrous carbonate has been formed in a reducing medium highly charged with carbonic anhydride. The iron in alluvial formations is invariably present as hydrated ferric oxide, which is generally supposed to have been brought up by the water springing from the underlying rocks. I f this explanation were correct, we should expect to fiiid crp*allised ferrous carbonate deposited in the caverns and fissures in these rocks, but as a matter of fact, the whole of the iron which they contain is in the state of hydrated peroxide. This would indicate' that the iron has really been derived from water percolating from above.Amongst the natural compounds of a metal, that with the greatest heat of formation should constitute the principal mineral of the parti- cular metal. If all minerals had been deposited from aqueons solutions of tolerably simple composition, it would follow from the laws of thermochemistry that there should only be one naturally occurring compound of each metal, but many minerals have been31 .NEtiALOGIdAL CHEMISTRY. 37 formed in very complex media and under extremely varied conditions, and these geological conditions have to be taken into account. All minerals may, however, be broadly divided into the folloN-ing types : those which have been formed in an oxidising medium ; those which have been formed in a reducing medium; those which have been deposited on a siliceous substratum; and those which have been deposited on a calcareous substratum.The heats of formation of the more important manganese com- pounds are manganous sulphide, MnS, 22.6 cal. ; manganous oxide, AhO, 47.4 cal.; mnnganous carbonate, MIiC0.3, 54 9 cal.; and manganese peroxide, MnOz, 58.1 cal.. These values are in complete ngrecment, with the fact that manganese peroxide is by far the most abundniit mineral of manganese, that manganous sulphide is very rare, whilst manganous oxide exists oiily in combination with the peroxide, and that manganous carbonate is a rare mineral, mainly. confined to veins and fissures, and existing only out of contact with oxygen. Tn all cases where the oxidation of the manganese is not complete this result is due to the non-permeable character of the minerals by which the manganese compound is surrounded.C. H. B. Cornpsition of Water from Uxiage (Isere), By E. PETJGOI! (J. Phurm. IS], 11, 241--245).-Berthier examined this water in 1823, and found the solid residue to be 5.76 grams per litre ; twenty p a r s later tllis became almost doubled in amount, and has smce remained constant. The following is the result of the author's analysis :- CaCO,. NaC1. KC1. CaSO,. N%S04. MgS04. N&.HAsO,. 0.388 6.000 0.402 1.145 1.255 0.609 0 002 SiOp H& Total. 0.01 4 0.010 9822 The total solid residue was 11.917 grams, the excess being due to water of crystallisation of the sulphates. The presence of minute traces of iodine and boric acid was ascertained, the latter hasriug been previously found by Dieulafait.Lefort has detected lithium,. rubi, dium, ferrous sulphide, sodium tkiosulpbate,. and organic matter. Sp. gr. 1.0084 ; dis.solved gases, nitrogen 19 c.c., carboriic anhydride, 3.2 c.c., a t 0" and i60 mm, The other coiistituents agree closely with those obtained by the auhhor. The probable origin of the water is discussed. The water is accompanied by enormous yuantitiej of gas, which is mainly composed of nitrogen and carbonic anhydride. J. T.20 ABSTRACTS OF CHEMICAL PAPERS.Mineralogic a1 C h ernis try.Absolute Hardness of Minerals. By F. PFAFF (Zeit. R ~ y s t .Min., 10, 528--531).-The author has made a series of experimentsto determine the absolute hardness of minerals. An accurate chisel-shaped diamond cutter was passed with constant pressure in the samedirection 100 or 1000 times over the face of the crystal, and thevolume thus removed estimated by weighing the crystal before andafter the experiment. A detailed description is given cf the instru-ment employed.Assuming that the hardness of two crystal planesis in inverse proportion to the volume of material removed, with t,hesame load and the same number of passings to and fro of the diamondOver an equal area, the hardness of minerals can then be expressednumerically, a given substance (talc) being taken as unit.B. H. BMiNERALOOICAL CHEMISTRY. 21The Gold Beds of Mount Morgan, Queensland. By R. L.JACK (DingZ. polyt. J., 258, 45).--These beds are situated about35 kilos. south-south-west of Rockhampton.The gold is distributedin hematite ironstone and in siliceous sinter. D. B.Copaline from Hiitteldorf, near Vienna. By G. Swam (Zeit.Kryst. illin., 10, 427).-In the slate of the Vienna sandstone, a fossilresin occurs in sharply angular fragments, or in sniall grains of8 mm. diameter. Its colour varies between light greenish-yellow andbrown. It is transparent to translucent. Several grains exhibitdistinct fluorescence. It is brittle, fusesat 160 to 165" to a clear liquid.; at 360" it becomes brownish-black,bard, with metallic lustre, .and at a red heat it burns leaving noresidue. B. H. B.Its density is less than 1.1.Pseudomorphs. By E. DOLL (Zeit. Rryst. Miw., 10, 423).-Theanthor describes pseudomorphs of iron pyrites after copper pyrites,from Kapnik, and pseudomorphs of tetrahedri te after copper pyrites,from FelsobLnya.In the pseudomorphs from Kapnik and Felsiibinya described, andin the pseudomorphs of iron :pyrites after copper pyrites from Musen,numerous spherical cavities were o bserxed, around which the ironpyrites is grouped.This the author regards as a characteristic struc-ture for many pseudomorphs.Galena with Octahedral Cleavage from Wermland. By H.SJ~GREN (Zeit. K r y s t . Min., 10, 507--508).-1a a specimen of galensfrom Nordmarks mines in Dr. Lundstrom's collection, the usualcubical cleavage is not developed. On breaking up the specimenirregular fragments are formed of a distinctly octahedral character.The ordinary cubical cleavage is developed after two hours' heatingat 200"; at 250" much more rapidly; and at 300" with still greaterfacility.Analysis gare the following results :-Pb. Bi. Ag. Pe. 8. Total.85.67 0.76 0.05 0.39 13-59 100-46B. H. B.The author is of opinion that the percentage of bismuth sulphide,which was also observed in the galena of Habach, may be the causeof the octahedral cleavage of galena. The galena, with octahedralcleavage, from Mt. Blanc, described by A. Brun (Abstr., 1883, 428),also gave on analysis 1 per cent. of bismuth sulphide.B. H. B.Tetrahedrite from the Alaska Vein, Colorado. By T.LIWEH (Zeit. Kryst. Min., 10, 488-489) .-The author has examinedcrystals of the new mineral from the Alaska vein, S.W. Colorado,described by Konig under the name of alaskite (Zeit.K r y s t . Min., 4,42), in order t o prove crystallographically whether the mineral reallybelongs to the isomorphous rhombic group of copper-bismuth glance,lead-arsenic glance, &c. The measurements, however, showed thecrystals to belong to the regular system; the mineral being evidentl22 ABSTRACTS OF CHEMICAL PAPERS.tetrahedrite. A qualitative analysis showed the presence of S, Bi,Sb, Pb, Ag, Cu, Zn, the elements given by Konig in his analpis of0 alaskite. The following forms were observed on the crystals : + %,202 404 30 02 2 ' , + L , - 2 2' B. H. B. - 202 + -,03003,m0, -- -Microscopic Character of Variegated Copper Ore from NewMexico. By H. BAUMHAUER (Zeit. Kryst. Min., 10, 447-450) .-Theauthor has examined, under the microscope, a specimen of bornitefrom Chloride, in New Mexico.He found that t,he compact bornitewas of a crystalline character, with inclusions of copper glance. Ontreating these inclusions with concentrated nitric acid, it was seenthat they consisted of a number of separate crystals, irregularlygrouped together. I n addition to copper glance, a second mineralwas observed here and there in the inclusions. This might possiblybe galena. Small patches of copper pyrites also occasionally occur inthe inclusions. In several places, the ore incloses small distinctlydeveloped crystals of quartz. B. H. B.Antimonite from Czerwenitza. By H. v. FOUT~LOX (Zeit. Kryst,Min., 10, 429).-Antimonite occurs in the red trachytic mother-rockof the opals, in the form of hemispherical radiated aggregates, 1 cm.in diameter.These are frequently covered with hyalite. Several ofthe hemispherical aggregates of antimonite consist exclusively of an ti-monite fibres ; others, however, are found on microscopic examinatioiito consist of antimonite with interstratified hyalit'e, which the authorregards as pseudomorphs after antimonite. Similar pseudomorphsare found a t the Josephis adit, in Klausenthal, near Eperies.B. H. B.Selenides from the Andes. By F. HEUSLER and H. KLIXGER(Ber., 18, 2556--2561).-Analysis of zorgite containing a con-siderable quantity of silver. The substances are not homogeneons ;analysis of the different parts gave-45 Cu. Pb. Co. Bi. Se. Total.I . . . . 19.20 12.43 35.70 traces - 32.77 100.0911.. , .27-49 25-40 17.10 0.39 - 25.54 99-92L--d111.. .. 15.87 36.15 1.73 46.25 100.00I V . . . . 19.16 35.77 3.45 41-62 100*00I and I1 clear bluish-green substance of silvery lustre. I agrees withthe formula Ag2Se,2PbSe,2CuSe. I11 and lV, darker samples ofbluish lead colour, are essentially selenides of silver and copper(comp. Pisani, Abstr., 1880, 440). A. J. G.Refractive Indices of Fluorspar. By E. SARASTN (Zeit. K r y s t .Min., 10, 523- 524).-The author has determined the refractiveindices of a fluorspar prism, with a refraction angle of 60" 4' 55". Atable of the results is given for the spectrum lines, A, a, R, C, D, F, hMISERALOGICAL CHEMISTRY. 23H, (Cd) 9, 10, 11, 12, 17, 18, 23, 24, 25, 26, (Zn) 27, 28, 2% (A]) 3%31, 32.B. H. B.Optical Properties and the Micro-structure of Corundrum.By A. v. LASAULX (Zeit. R ~ y s t . Min., 10, 346--365).-Corundum iswithout doubt an optically uniaxial mineral crystallising in the hex-agonal system. Disturbances in the regular optical behaviour dependon the nature of the growth and the structure of the corundumcryst'al. The crystals occurring in volcanic rocks appear, as a rule,to have a more uniform constitution and a more regular optical beha-vionr than those found in the older crystalline rocks. The opticaldisturbances appear tliroughout to be connected with the more orless distinctly developed sbructural faces parallel to R, wP2, and OR.The concentric structure in the direction of one or other of theseplanes determines the cleavage, which is developed in the direction ofR alone, or R and OR, or mP2 and OR, or all bhree planes a t the sametime, more or less perfectly.The cleavage is not dependent on thetwin lamellae present, but on the other hand the latter are dependenton the presence of the structural planes which determine the cleavage.But both appear simult,aneously almost always. In this- case, struc-tural and twin planes are identical. In the direction of mP2, theplane of symmetry, a twin formation is not possible ; in bhe directionof OR it is entirely unknown, The optical disturbances hi the zonelamell= bounded by the structural planes are, however, of two kinds :-1. Optical disturbance is effected by tension in the zones of thecrystal.2. It occurs in consequence of interpolated twin lamell=.Lastly, optical disturbances also occur in corundum crystals, in con-sequence of processes of alteration, producing granular, laminated,or fibrous products in the interior of the crystals. Jn this case, how-ever, a regular interference figure is not exhibited. B. H. B.Corundum in Graphite. By H. WICHMANN (Zed. Kryst. Min.,10, 425).-On the surface of the graphite of Muhldorf, near spit^,in Lower Austria, small crystals of corundum occur. The crystalsattain a thickness of 0.5-6 mm., and a length of 7-25 m u . Theyare of a red to blue colour, rarely grey, but always clouded with inclu-sions. The translucent crystals prove to be biaxial, with a ratherlarge axial angle.Gahnite and Epidote from Rowe, Massachusetts.By A. G.DANA (Zeit. K7yst. Xi)! ., 10, 490 -492).-With iron pyrites, copperpyrites, and quartz, the author found at Davis' mine, Rowe, frag-ments of gahnite, which on analysis gave the following results :-Al,O,. Fe,O,. FeO. MnO. MgO. ZnO. Si02. Total. Sp. gr.54 83 3.00 3.37 iirace 1.93 36.92 0.53 100.58 4-53The following minerals also occur associated with the gahnite :-Ilmenite, apatite, rutile, sphalerite, garnet, calcite, green crystals of;t triclinic felspar, and epidote. The epidote occurs in short prisms,opaque, and of a greenish-grey colour. Analysis gave the followingresults : -B. 11. B24 ABSTRACTS OF CHEMICAL PAPERS.SiO,. A1,03. Fe20,. MnO. MgO. CaO. Alkalis. H20. Residue. Total.38.20 24.62 12-20 0.57 0.13 21-59 0.37 2.16 0.35 100.19Goethite from Pitkaranta, in Finland.By M. WEIBULL (Zeit.Kryst. illin., IQ, 511-$12).-The author describes specimens of quartzaiid fluorspar w.ith..cavities lined with rock crystal and haematite, onwhich needles land radiated, aggregates of goethite were crystallisedout. An analysis of the goethite gave 89-65 per cent. of ferric oxide,and 10.50 per cent. of water. The mineral is therefore a very puregoetliite. B. H. B.Zircon in Sbsratified Rocks. By F. SANDBERGER (Zeit. Kryst.$!in., 10, 405).-The author has observed transparent crystals of~ r c o n in the granite of Schapbach, in the Black Forest, of Windeck,near Weinheirn, of Heidelberg, Ilmenau, of the Luisenburg, nearWunsiedel, Nabburg and Worth, near Regensburg.The crystalsexhibit exclusively the combination mPm. Transparent zircons arealso found in gneiss and mica-diorites, and in the porphyry of theWagenberg, near Weinheirn, Microscopically small zircons of thesame form are widely distributed in the sedimentary rocks, the mate-rial of which is mainly derived from the older rocks ; for example, iiithe variegated sandstones of the Black Forest and Spessart, in car-boniferous sandstone, in the Upper Keuper sandstone, and in thesands of the Valley of the Maine.B. H. B.B. H. B.Boracite. By H. BAUMHAUER (Zeit. K ~ y s t . 3&, 10, 451-457).-The author brings forward further arguments to prove that boraciteat; the ordinary temperature, in the state in which it is met with innature, does not crystallise in the regular, but in the rhombic system.Uranothallite. By A .BREZINA (Zeit. Kryst. &!in., 10, 425-426).-Crystals of uranothallite recently obtained at Joachimsthal, gave,for the rhombic crystals, the axial ratio a : b : c = 0.954 : 1 : 0.783.The analysis gave the following results :-uop cop. CaO. FeO. HzO. Total.B. H. B.35.45 23-13 16.28 2-48 22.44 99.78corresponding with the formula 2CaC03 + UC20, + 10H20.B. H. B.Occurrence of Hornstone and Barytes in the PorphyryDistrict of Teplitz. By G. LAUBE (Zeit. K~yst. A&., 10, 421).-I n a description of. a crystal of barytes from Teplitz, in Bohemia(Zeit. Kryst. Mi72., 9, 2 2 l ) , Becke stated that the crystal was depositedfrom the'Teplitz mineral water, which, according to the analyses ofSonnenschein, contains no barytes.This statement the author correctsby showing that barytes occurs in mineral spring fissures only wherethey traverse the Cenomanian hornstone-conglomerate occurring inthe neighbourhood of Teplit z. From these fissures honey-yellowcrystals of barytes have been long known. The Teplitz springs,however, do not contain barium. Only in the Neubad spring havMISERALOGICAL CHEMIST kT. 25traces of ba,rium been found.conglomerate conhaining baryt)es.This spring passes through hornstone-B. H. B.Halotrichite and Epsomite from the Falu Mine. By &I.WEIBULL (Zeit. Kryst. Min., 10, 512).-In two portions of the Falumine, where the degree of moisture is low, and the temperaturerelatively high, sponge-like ma.sses occur of a recent mineral, whichappears to be a mixture of epsowite and hnlotrichite.The sp. gr. ofthe mixtnre is 1.77. The analysis gave results corresponding withthe formula-2(MgS04 + 7%0) + (FeZnCa)(AlFe),(SO& -t 22H20.B. H. B.Turquoise from Nischapur in Persia. By E. TIETZE (Zeit.E r y s t . iklin., 10, 428) .--The mother-rock of the turquoise of Nischapuris, contrary to all former descriptions, a porphyritic trachyte. I nthis, and in a breccia formed of angular fragments of the frachyte, theturquoise occurs in veins, 2 to 6 mm. thick, or in irregular patches.In the trachyte, pseudomorphs of turquoise after orthoclase occur.Turquoise is also found in shapeless fragments in the alluvium in theneighbourhood of the trachyte rocks.Berzeliite.By L. J. IGELSTROM (Zeit. Kryst. ikfin., 10, 516-517).-The author notes the discovery of berzeliite, hitherto foundonly at Lingban, a t the Moss mine in Wermland. An analysis gavethe following results :-B. H. B.As,O,. CaO . MgO. Mn, Pb and C1.57.80 25.25 16.95 tracesThis corresponds with Dana's formula for berzeliite-(CaMgRfn) 10A~6025. B. H. B.Xanthoarsenite, a New Mineral from Oerebro. By L. J.IGELSTROM ( X e i t . Kryst. Min., 10, 518-519).-l'he new mineraloccurs at a small iron mine 6 miles east of Grythytta. Its colour issulphur-yellow to orange. In thin splinters, it is translucent. Beforethe blowpipe, it melts to a black glass, giving a strong odour ofarsenic.As,O,.MnO. FeO. MgO. CaO. H,O.33.26 43-60 3.11 6.08 1-93 12.02Analrsis gave the following results :-B. H. B.Manganostibite, a New Mineral from Wermland. EyL. J. TGELSTROM (Zeit. Kryst. Min., 10, 519).-This mineral occurs a tthe Moss mine, in small, black, rhombic crystals. An analysis of0.54 gram gave the following results :-Sba06. AszO,. MnO. FeO. CaO. MgO. Total."24.09 7-44! 55.77 5-00 3.62 3.00 99-92* The figures given only add up t o 98.92.B. H. B26 ABSTRACTS OF CHEMlCAL PAPERS.Vanadates and Silver Iodide from New Mexico. By F. A.GemH and G. v. RATH (Zeit. Krysf. Min., 10, 458-474).-Quiterecently new workings a t the Sierra Grande Mine, Lake Valley,Donna Anna Co., New Mexico, have yielded a number of highlyinteresting and rare minerals, which have been examined chemicallyby F.A. Genth, and crystallographically by G. v. Rath.Vanadinite, from the Sierra Bella Mine, Lake Valley, gave thefollowing results on analysis :-C1. P,05. V,05. As205. PbO. Total.* Sp. gr.I.. . . 2.39 0-57 17-37 0.24 79.43 100.00 -11.. . . 2.49 0.39 17.44 1.33 78.31 100.26 6.862I1 is the analysis of vanadinite from the Sierra Grande. Thiscorresponds with the formula Pb,Cl[ (VAsPb)0,I3 ; whilst analysis Igives a small excess of lead, probably present as cerussite.Lead Ai*sen,io-vanadate-End 1ichite.-An analysis of a supposedvanadinite from the Sierra Grande gave the following results :-SiO,. Fe203. CaO. C1. As205. V20+ PbO. C02,H,0. Total.76-44 0.99 0.30 0.44 2.16 1-60 15.94 C2.131 100.00The mineral has thus the composition of equal mols.of mimetiteand vanadinite : Pb5C1(AsOJ3 + Pb5C1( VO,),. This mineral theauthors believe to be new, and propose for it the name of endlichite,after the director of the Lake Valley mines.Desc1oizite.-Very fine red and brown crystals have recently beenfound a t the Sierra Grande. The mean results of three analjses oft'he red (I), and of three analyses of the black variety (11) gave thefollowing results :-PbO. CuO. ZnO. MnO. FeO. Ae205. V,05.I1 , . . . 36-36 0.87 13.91 2.74 0.30 0.50 21.35P205. H,O. Total. Sp. gr.I .... - 2.37 99 49 6.106I1 . . . . 0.04 3.39 99.46 5.848After subtracting the impurities shown by the black descloizite, itasanalysis agrees vary well with that of the pure red, the compositionbeing expressed by the following formula :-Pb,(HO) (V,As,P)O, + (Zn,Mn,Cu,Fe)z(HO)(V,As,P)O,.I .. . . 56-12 1.10 17*&1 0.49 0.15 0.20 21.65No indunium is present in the vanadates of Lake Valley.On the ne_w descloizite crystals, thefollowi~ig form? were observed:-P, 2P2, gP3, $Pm, ZPm, COP, mP3, cnP03, m P q OP, with therhombic axial ratio, a : b : c = 0.6367 : 1 : 0.8046.Silver iodide.-Pure silver iodide is frequently found accompanyingthe vanadates of the Sierra Grande. It occurs with calcite and reddescloizite in yellow, indistinct crystals and crystalline masses ; andwith vanadinite and black descloizite i n very small, indistinct, roundedcrystals. B. H. B.* The figures giren only add 1113 t o 93.96BIINERALOGI(I1AL CHEMISTRY.27Minerals of the Pegmatite Vein at Moss. By W. C. BROGGER(Zeit. Z(ryst. Min., 10,494-496).--The author gives a long list of theminerals occurring in the pegmatite vein at Moss, the remarks on thenew mineral atlneyodite being of special interest. This mineral isblack with metallic to resinous semi-metallic lustre. H. = 6 ; sp. gr.5.7. Analysis gave the following results :-Nb,O,. SnO?. SiO,. Zr02 UO,. Tho,. Ce oxides. Y oxides. PbO.48.13 0.16 2.51 1-97 16.28 2.37 2.36 7.10 2.40FeO. MnO. CaO. MgO. K,O. NasO. Also,. H20. Total.3.38 0.20 3.35 0.15 0.16 0.32 0.28 8.19 99.51corresponding with the foimula2R,NbL0,(+ 5H20 + +SiO,>.The mineral, therefore, resembles samarskite, from which it differscrystallographically. The axial ratio is rhombici a : b, : c =0.40369 : 1 : 0;3610,3.The fojms observed yere,_mPm, mPm, OP,WP, mP3, mP5,2Pm7 $Pm, Pm, P, 2P2, 2P2, 3P3,2P,B. H. B.Quartz from Burke, North Carolina. By G. v. RATH (Zeit.Kryst. ZCIin., 10, 475-487) .-A description of peculiar crystals fromthis locality.Opal from Nagasaki, Japan. By H. SJOGREN (Zeit. I(ryst. Min.,10, 508).-The mineral is of a yellowish-brown to chesnut-browncolour, and possesses the usual characteristics of opal. Under themicroscope, 110 trace of organic structure could be detect'ed. Analysesof material dried a t 133" (I), and of undried material (11), gave thefollowing results :-H,O. SiOs. Fe203. A1,03. MgO. Total.I . . . . 3.59 88-87 5.26 1-84 0.32 99.88I1 . . .. 8-87 84.36 4.99 1.74 0.30 100.26The latter analysis corresponds with the composition of menilite,H2Si30s. B.H. B.Change in Colour in Felspar due to the Action of Light.By E. ERDMANN (Zeit. K ~ y s t . Min., 10, 493).-From the pegmatiteveins of the Ammeberg zinc mine, the author collected specimens ofamazonite, with which he made the following experiments :-A largefragment was broken into three parts, 5 to 10 cm. long, the freshfracture showing a pale greenish-grey colour. Of these pieces, onewas packed up in black paper and kept in a dark place; the twoothers were exposed to the action of sunlight, one having a strip ofblack paper 10 mm. wide pasted on and varnished, the other havinga strip of the same width varnished to exclude air and moisture, butnot light.The two specimens were exposed to the action of the sun,air, and rain for 74 days. It was then found that the original pal28 -4BSTRACTS OF CHEMICAL PAPERS.green colour had become a deep emerald-green ; the portion protectedby the black paper and the specimen kept in the dark room havingremained unaltered. The layer of varnish had cracked, so that it couldnot be decided whether the change was due to air and moisture, or tolight alone. A second experiment was then made. A piece of theunaltered felspar was broken up, and small pieces placed in five tubesof different colours (black, blue, yellow, pale emerald-green, andcolourless). The open ends of the tubes were then sealed, withoutheating the felspar, and the tubes exposed to the action of light for10 months.On opening the tubes, the felspar in the colourless tubewas found to be of a deep emerald-green colour; the felspar inthe green tube was less altered, still less in the yellow, andinappreciably in the blue, whilst in the black tube it was quiteunaltered. The change in colour is due, therefore, to the action oflight alone. B. H. B.Apophyllite from Wermland. By L. J. IGELSTROM (Zeit. Kryst.Min., 10, 517).-At the Nordmarks mines the author found, inaddition to the ordinary apophyllite in crystals, concentrically radiatedglobnlar masses of the same mineral, 2 to 3 em. in diameter. Anincomplete analysis gave the following results :-Si02. CaO. MgO. K20,Naz0,B’. H,O. Total.52.00 23.20 1.30 7.10 16.40 100.00B. H. B.Chemical Composition of the Amphiboles.By F. BERWERTH(Zeit. K~ysf. Mim., 10, 406-409).-1. li.emoZife.--The mean of twoanalyses of tremolite from St. Gottharcl gave the following results :-SiO,. d1,0,. FeO. CaO. MgO. H,O. Total. Sp. gr.58.40 0.56 0.26 13.63 24.82 1.85 9952 3-02Making allowance for the talc mixed with the specimen analysed,the analysis corresponds with the formula( CaSi03) (MgSi03) (H2Si03).2. Actindite.-The author gives the formula for pure actinolite as I 5CaSi039MgSi032HzSi033. Arfvedsonite, from the Nuriasornausak Mine in Greenland, gaveon analysis the following results :-Si02. A1,0,. Fe,O,. FeO. CaO. K20. Na20. HzO. Total. Sp. gr.47-08 1.44 1.70 35.65 2.32 2.88 7.14 2.08 10029 3.45The author assumes that muscovite is mixed with the mineralanalysed, and that the formula for pure mfvedsonite is13FeSi0,CaSiO,4Na2 Si032H2SiOMINERALOGICAL CHEMISTRY.294. Alunzina-hornbleizd~, from Vesuvius, gave the following analj ticalresults :-SiOP A120,. Fe203. FeO. CaO. MgO. KJ3.39-80 14-28 2-56 19.02 10.73 9-10 2.85Ka20. HaO. Total. Sp. gr.1.79 1-42 101.55 3.29The author is of opinion that, as the amount of mica mixed withthe hornblende is very small, the hornblende crystals were built up ofcalcium silicate and meroxene moleciiles, and assumes that at first thetendency to form meroxene predominated, but that the regular develop-ment of the merosene was disturbed by the calcium silicate cominginto play. By the calcium silicate and memxene crystallising toge-ther, a hornblende crystal resulted as terminal product.5.Alumina- hornblende (Pargasite), from the granular limestone ofPargas, had the following composition :-F. Si02. Al,03. PeO. CaO. MgO. K20.1.66 42.97 16.42 1.32 14.99 20.14 2-85RTa30. H20. Total. SP. gr.1-53 0.87 102.75 3.11Subtracting the 35.91 per cent. of mechanically mixed phlogopite, theformula, for the pure pargasite is I 8Si3A1,0,29SiCa2047 Si hl g204SiHp046. Glaucophune, from Zermatt, gave the following results onSiO> A1903. FeO. CaO. MgO. Na,O. H,O. Total. Sp. gr.58.76 12.99 5.84 2.10 14.01 6.45 2.54 102.69 3 04analysis :-The quantity of paragonite admixed could not be determined.Alterations of the Garnets in the Amphibole Schists of theTyrol. By A. CATHREIN (Zeit.K ~ y s t . Min., 10, 433--446).-1n rocksfrom the Stamser Alps, the author has observed garnets altered intoscspolite, epidote, oligoclase, hornblende, saussurite, and chlorite.B. H. B.B. H. B.Vesuvian Humite, Chondrodite from Nyakopparberg, andHumite from Ladugrufvan. By F. C. v. WIHGARD (Zeit. Anal.Chem., 24, 344-356).-The above minerals (with the exception ofthe Ladup-ufvan humite) showed no trace of alteration to serpentine.The fluorine was determined by the direct method of Fresenius, exceptin the case of the Vesuvian humite of type 11, and that from Ladu-grufvan, where the small quantity of material would only allow of th30 ABSTRACTS OF CHEMICAL PAPERS.use of Berzelius' process. After drying a t 110", the minerals stillcontained hydrogen.This was determined by igniting with leadoxide and weighing the expelled water. The following are theanalytical results :-I. Vesuvian humite, type I, or hurnite of Descloiseaux.11. Vesuvian humite, type 11, or chondrodite of Descloiseanx.111. Vesuvian humite, type 111, or clinohnmite of Descloiseanx.IV. Chondrodite from Nyakopparberg : a, pale wine-yellow ; b,Pale win e-y ellow.Pale brownish-yellow or greyish-brown.honey-y ello w.V. Humite, type I, from Lndugrufvan.SiO,. MgO. FeO. Fe,03. MgF2. HzO. Total.1 . . , . . . 35-49 49.47 4.32 - 9.20 1-45 99.9311 .. . . . . 3.3'49 52.87 3.80 - 8.39 1-37' 9992111 . . . . . . 33.40 45.65 9.63 0.82 9.25 1.41 100.16a. 33.90 47.65 7.76 0.11 9.10 1.31 99.83b. 31.56 37.54 18.67 2.01 9.10 1.31 100.19V .. . . . . 35.26 50.51 3.51 - 7.70 3.07 100*05The completely unaltered condition of the specimens, and the fact)that the water was not expelled below a red heat, negative the sup-position of v. Rath that the deficiency in the older analyses was dueto water of hydration, and require the hydrogen to be regarded asexisting in the form of hydroxyl, replacing fluorine isomorphouslg.The fluorine determinations (of which the above numbers are theaverages deduced from numerous concordant results) do not exhibitthe wide variations found by other analysts, and, in fact, with theexception of 11, in which i t is assumed that the fluorine is below thetruth, of IVb, which is rejected, and of the excess of water inV, dueto an obvious partial alteration, all these numbers (after calculating theiron as magnesium) lead to the identical formulaIV ...{for all the three types. M. J. S.Isomorphous Silicates. By C. RAMMELSBERG (Chew,. Centr.,1885, 687--688).-The author has endeavoured, by a series of experi-ments, to add to the knowledge of the chemical nature of themembers of the scapolite group. All the members of this group areperfectly isomorphous. They are called by various names, but quali-tatively their composition is the same ; they are silicates of alumina,lime, and soda. Only in one member, humboldtilite, do iron andmagnesia occur to a considerable extent. There is no soda-free scapoliteknown, corresponding with anorthite, nor a lime-free scapolite, corre-sponding with albite, which, like the above-mentioned minerals of thefelspar gronp, could be regarded as terminal members of the series.The composition of the various members of the group, however,is very different; the proportion of acid amounts to 40 to 60per cent., that of lime varies from 24 to 4, whilst the amount oMIXERALOGICAL CHEMISTRY.31soda amounts to 2 to 10 per cent. With the variations in the atomicproportion of Na : Ca : A1 : Si, it appears desirable to assume Ca = 2R,A1 = 6R, and to calculate the ratio R : Si. In this way the authorfound that the scapolite group includes: (A) semisilicates ; (B) com-binations of normal and semi-silicates ; (C) normal silicates ; and (D)combinations of normal and quadri-silicates. He concludes that inthe scapolite group only the simplest silicates occur, namely :-Normal. .. . . , . . . .Semisilicates . . . .Quadrisilicates . . .and combinations of any two of them. I n group B, which includesthe majority of cases, combinations of 1 and 6 mols.,of 1 and 3 mols.,of Z and 1 mol., and of 4 and 1 mol. of normal and semi-silicate, arefound. The combination of normal and quadri-silicate (group D)consists of 3 and 1 mol. B. H. B.Mineralogical Notes from Bohemia. By R. RAFFELT (Zeit.Kryst. Min., 10, 42l).-In fissures and cavities in the basalt of theE ulenberg near Leitmeritz, the author found analcime, chabasite,phillipsite, and thomsonite, with aragonite and calcite. The analcimeforms thin, crystalline crusts exhibiting the form 202. Chabasiteoccurs in yellow, twin crystals ; phillipsite also occnrs in twin crystals.On the latter are frequently planted crystals of thornsonite, with thefollowing composition :-Si02.Al,O,. CaO. Na,O. HzO. Total.38.44 31.48 13.60 3.53 12.93 99.98N%SiO, ; CaSiOs ; AISi,O,.Na,Si04 ; Ca2Si04 ; A12Si3012.Na,Si,O, ; CaSi20, ; AlS&O,,,B. H. B.Empholite, a New Mineral from Horrsjoberg in Wermland.By L. J. IGELSTROM (Zeit. Kryst. Min., 10, 521).--'l'his new mineralforms white or yellowish, translucent crystals, and radiated aggregatesin damourite and pyrophyllite in gneiss. The minsral crysta_llises inthe rhombic system with the planes mP, d 0 3 , mP2, and mP3. Theplane of the optic axes is parallel to the brachypinacoid ; the acutebisectrix is parallel to the brachydiagonal, positive ; the obtusebisectrix is parallel to the vertical axis.In appearance the mineralresembles diaspore ; H. = 6. Analysis gave the following results :-SiO,. A1203. MgO,CaO,FeO. H,O. Total.51-70 31.52 4-60 12.18 100.00(Compare Abstr., 1885, 31.)By L. J. IGELSTROM (Zeit. Kryst. Min., 10, 522).-An analysis of the mineral discovered by the author in 1860, andnamed persbergite, shows it to be a mineral resembling falunite. Theanalytical results were as follows :-B. H. B.Persbergite.Si02. Al,03(Fe,03). Mg0,CaO. H20. Total.41-20 2 7-50 18*LO 13.08 1UO.00B. H. B32 ABSTRACTS OF CHERlICAL PAPERS.Minerals from the Mica Diorite of Christianberg, Bohemia.By G. STARKL (Zeit. IZryst. Him, 10, 427).-The minerals examinedwere biotite, hornblende, plagioclase, and apatite.The three firstminerals on analysis gave the following results :-Si02. Al,03. Fez03. Cr203. FeO. CaO. MgO. K20.I.. 39.53 13.45 8.06 0.14 4.99 3.38 22.52 4.13111.. 65-54 21.74 trace - - 2.14 trace 3.32N8.20. H2O. SP. gr.I .......... 1.22 1.49 2.81I1 .......... - 1.04 2.9%I11 .......... 7.75 0.35 2.5711.. 5.3.8:3 3.78 3.50 0.08 6-83 10.32 19.49 -Corresponding with the formula+-I. Biot,ite. ..... 2[ (HzNazK2)zSi04] + 11 [ ( FeCaMg),Si04]11. Hornblende . 15(RSiO,) + l(R;"Si309).111. Plagioclase . . 2(&~Al~si~o,~) + 6(Na2A1,Si6Ol6) + 1( Ca2A14Si40,6).Chemical Constitution of Staurolite. By W. FRIEDL (Zeit.K r y s t . Mi%., 10, 366-373).-Analyses of staurolite (1) from St.Gottliard and (11) from Tramnitzberg, in Moravia, gave the following+ 3[ (~2FezCr2)zSi3O,z].B. H.B.results :-Si02. A1,03. Fe203. FeO. MgO. H20. Total.I . . 28.1.5 52.17 1.70 13.84 2.54 1-63 100.03I1 . . 28.19 52.15 1.59 14.12 2.42 1.59 100.06Both of these analyses correspond with the formulaH4( FeMg) 6( AlFe) 24SiiiOs6, O r (FeMg)6A&(AIO) m( OH),( SiO,) 11.This formula, based on analyses of rna'terial proved to be pure bymicroscopical examination, differs from Rammelsberg's formula forstaurolite by Q mol. SiO,. And the ferric oxide, passed over byKammelsberg, is taken into account in the new formula. Anestimate of the value of the two formulst: may be formed from thefoIlowing comparison of the actual and calculated results :-I, New staurolit e formula, B4 (A1 ,-$sFe) 24 (iB'e, M g) Si11066.Si02.Al,03. FezO3. FeO. MgO. HzO. Total.Calculated . . 28.38 51.87 1.68 13.93 2.58 1.55 99-99Found ...... 28.17 52.17 1.65 13.98 2.48 1-61 100.0611. Old staurolite formula (according t o Rammelsberg, taking intoaccount the percentage of ferric oxide discovered by the author),Hz(~Fe,~~g)~(Al,-a,Fe) 1~Si~034.SiO,. Al,03. Fe203. PeO. MgO. H20. Total.Calculated.. 30.18 50.58 1.64 13 58 2-51 1.51 1OU.t)OFound.. .... 29.46 52.29 - 13.42 2.29 1.60 99-01lINERALOGlCXL CHEMISTRY. 33The percentage of aluniina found by Rammelsberg exceeds thecalculated amount by 1.71, whilst the silica percentage is 0-72 lessthan the calculated.On comparing his analysis with that of the microscopically testedmaterial, it is evident the staurolite he employed contained somequartz.It may consequently be assumed that staurolite has the formula ofa basic silicate :-(MgFe)&,( AIO),( OH),( siod 11 = &(Mg,Fe)6( A1Fe)24Si,,0,6,whichrepresents the simple oxygen ratio of 2 : 1.Pycnophyllite from Aspacg.By G. STARKL (Zeit. Krpf. Min.,10, 427--428).-The author gives the name of pycnophyllite to acompact, finely laminated substance, which fills the fissures of atalc-mica schist, south-east of Aspang. The mineral is of a preencolour, is greasy to the touch, adheres to the tongue, has a resinouslustre, H. = 2, sp. gr. 2.7!16, is easily split up parallel to one plane.Thin leaves are translucent, biaxial, negative. In composition themineral mast resembles hygrophilite o r pini te.The analjses ofspecimens from two localities in the neighbourhood of Aspang gavethe following results :-SiO,. d1,03. Fe&. FeO. CaO. MgQ. K20. Na20. H20.48.88 -29.37 2.38 0.51 1.24 2.67 6.51 3.34 4.6250.09 26.47 3.66 - 0.44 3.93 10.77 4.61B. EI. B.Igelstromite from Delarne. By M. WEIBULL (Zeit. Kryst. Mi%.,10, 511).-This mineral, formerly desc~ibed by the author (Abstr.,1884, 409), from the Silferberg mines, has been recently found fourmiles further to the south-west in the Hillangs mines. The depositcousists of magnetite with mangnnocalcite, silicates rich in man-ganese (igelstromit e, actinolite, and gnrnet), arsenical pyrites, andmagnetic pyrites. An analysis of the igelstrornite gave the followingresnlts :-B.H. B.-SiO?. FeO. MnO. MgO. CsC03. Total.28-76 48.59 18.57 1.93 2.25 100.15corresponding with the formula-2(FeMg)2Si04 + (MnMg),Si04.B. H. R.Minerals of Vester-Silfberg. By M. WEIBIJLT, (Zeit. TG-yst. Mi?? ,10, 512-515).-The author gives a detailed description of a numb, L'of minerals occurring a t Vester-Silfberg. Manganocalcite from theStollberg gave on analysis the following results :-CaO. MnO. FeO. MgO. C02. Insoluble. Sp. gr.46.22 6.98 3.01 0.22 (42.86) 0.71 2.804WmeRponding with the formula 6Catc03 + (MnFe)C03. The mineralVOL. L. 34 ABSTRACTS OF CHEMlCAL PAPERS.thus approximates closely to Breithaupt's so-called spartaite. Ananalysis of manganese-hisingerite, an alteration-product of igel-stromite, gave the following results : -Si02.Fe,03. Mn,03. Al,03. MgO. CaO. H20. Total. Sp. gr.37-09 34.34 15.50 1.39 2.62 1.92 7.81 100.67 2.469An analysis of silfbergite gaye-Si02. FeO. MnO. MgO. CaO. A1203. Ignition. Total.49.50 30.69 8-24 8.10 2.02 0.69 0.40 99.64corresponding wit,h the formula (FeMnMgCa)Si03.The author further mentions the occurrence of magnetite, igelstriim-ite, iron-rhodoni te, and manganese-hedenbergite (compa,re Abstr.,1884, 409). B. H. B.Manganese Minerals from Wermland. By L. J. IGELSTR~M(Zeit. Kryst. Min., 10, 519-521) .-The manganese minerals of theso-called steel ore mines of Giisborn in Wermland, axe manganesesilicates, and are largely employed in steel making. The author hasmade several analyses of these silicates, the results being asfollows :-R i 0 2 .MnO. FeO. CaO. MgO. &03. Fe,O,. Ignition. Total.2.10 100*0011. 47.00 31 20 10.60 5.70 2.50 - - 0.80 97.81111. 38.63 13.00 - 19.80 - 8.20 21.90 - 101.53I. Rhodonite ; 11. Rhodonite, with grains of magnetite; 111.A yellow manganese silicate gave the following analytical results :-I. 42.37 40.63 6.80 8.10 - - -brownish and manganese garnet.Total insolubleSiO,. FeO. MnO. CaO. in acids.38.35 14-05 29.52 10.52 92.46Total solubleMnC03. FeC03. CaCO,. in acids.3-70 2.01 1-36 7-07B. H. B.Chemical Composition of Katapleite. By A. SJOGREX (Zeit.Kryst. M h . , 10, 509-510).-The mean of two new analyses of kata-plgite is as follows :-SiO,. ZrO2. FeO. CaO. Na20. H20. Total.44-13 32.00 0.19 5.56 8.52 9-26 99.66The author, therefore, concludes that the formula of kataplgite is(Na.J3aFe)Si03 + ZrSi20s + 2H,O.B. H. B.Two New Norwegian Minerals. By W. C. BR~GGER (Zeit. Kryst.Min., 10, 503-504).- I. Lausnite. Monosymmetrical. Axial ratioa : b : c = 1.0811 : 1 : 0.8153 ; B = 71" 24+', with the combinatio3IINERALOGICXL CHEMISTRY. 35mP, mP2, mPm, 0332~0, - P, - PWO. The optic axial plane is theplane of symmetry, the acute bisectrix forming with the vertical axisan angle of 20y. Cleavage perfect in the direction of the ortho-pinacoid. Colour chesnnt-brown to yellow. Slightly translucent.Analysis gave the following results :-33.71 31.65 5.64 5.06 11-00 11.32 1-03 99.41 3.51This very rare mineral was formerly regarded by the author itsmosandrite, which it closely resembles.2.Cuppe2enite.-A greenish-brown mineral i n thick prismaticcrystals, translucent to semi-transparent. Hexagonal ; axial ratiou : c = 1 : 0.43010 ; combination, COP, P, 3P, OP.550,. ZrO,. Fe203. MnO. CaO. Na,O. Ignition. Total. Sp. gr.Analysis gave the following results :-SiO,. B203. Y20,. (LaDi),03. Ce2@. Tho2. BaO.14.16 (17.13) 52.55 2-97 1.23 0.79 8.15CaO. Na,O. K20. HzO. Total. Fp. gr.0.61 0.39 0.21 1.81 100~00 4.407B. H. B.Barium Sulphate as a Cementing Material in Sandstone.By F. CLOWES (Clzem. News, 52, 194).--In cerhin New Red Sand-stone beds in the neighbourhood of Nottingham, known as Staplefordand Bramcote Hills, and the Hemlock St,one, the cementing materialhas been shown by the author to be crystalline barium sulphate.TheHemlock Stone is mushroom shaped, and whilst the- lower portion iscalcareous sandstone, the upper portion is not, but contains baviumsulphate, to which fact most probably the stone owes its sha,pe. Thebarium sulphate occurs in some of the beds in streaks, patches, andlarge and small more o r less spherical masses ; the intervening ssndbeing loose, weathered surfaces appear honey-combed or mammellated,and in one case yield pebble-like masses of sand held togwther bybarium sulphate. D. A. L.Weathering of Sandstone. By J. STOKLASA (Landw. Versuchs-Xtaf.,1885,203-214).-The sandstone examined contained 41 per cent. ofquartz, and had a sp. gr. of 2.3-2.5 at 17". The changes which thisclass of stoue undergoes may be thus classified : oxidation of the ferrouscompounds (yellowing) ; partial solubion of carbonates ; loss of halfthe total calcium carbonate with relative increase of silicates andqiiartz; and final pulverisation of the mass.The analytical tablesshow clearly the conversion of insoluble into soluble compounds,especially in the case of the phosphates which rapidly become solublein acetic and citric acids. E. W. P.Application of Thermochemistry to Geology. By DIEULAFAIT(Compt. rend., 101, 609-612, 644-64G, and 676--ti79).--The objectof the author's investigations is to ascertain how far the main facts ofgeology can be explained by thermochernical laws, the inquiry beingd 36 ABSTRACTS OF CHEMICAL PAPERS.limited in the present papers to the formation of minerals at theordinary temperatures from subslances in aqueous solution.develops + 26.6 cal.From a consideration of the following reactions-2Fe0 + 0 = Fe,O,,2Mn0 + 0, = 2Mn02, 9 , + 21.4 9 ,2Fe0 + 2C0, = 2FeCO,, ,t + 10 0 9 )21In0 + 2C0, = 2MnCO3, ,, + 13.6 ,,it would follow that when oxygen and carbonic anhydride, both in ezcesc,come in contact with silicates or other minerals containing ferrous andmanganous oxides, the latter will be converted into ferric oxide andmanganese peroxide respectively, and no carbonates will be formed.If, however, the carbonic anhydride and oxygen come in contact withthe minerals slowly and in quantity insufficient to completely trans-form both oxides, the oxygen will combine mainlv, if not entirely,with the ferrous oxide, and the carbonic anhydride, being unableto cmbine with the ferric oxide thus formed, will .unite with themanganous oxide in preference to uniting with the still un-altered ferrous oxide.The products will, therefore, be femic oxide,which is insoluble, and manganous carbonate, which is distinctlyeoluble. If the two gases are dissolved in water percolating throughprimary rocks, the issuing water will contain manganous. carbonate inrelatively much greater proportion than in the original rock, and it iseasy to see that this explains the formation of manganese I mineralscomparatively free fi-om iron, from rocks in which iron is present inconsiderable quan1,ity.Since the heat of formation of ferric oxide is so much greater thanthat of 'ferrous carbonate, it follows that the latter can only beformed in a reducing medium, and can only remain unchanged solong as it is protected from the action of oxygen.Naturtil ferrouscarbonates may be divided into two groups : spathic 'iron, which iscrgsta7listtd, and exists in the oldest rocks as well as in comparativelyrecent formations ; and lithoidal ferrous carbonate, which is confinedt o the carhon7ferous horizon. The formations in whibh this lithoidalferrous carbonate occurs, are of estuarine origin, and hence the ferrouscarbonate has been formed in a reducing medium highly charged withcarbonic anhydride.The iron in alluvial formations is invariably present as hydratedferric oxide, which is generally supposed to have been brought up bythe water springing from the underlying rocks. I f this explanationwere correct, we should expect to fiiid crp*allised ferrous carbonatedeposited in the caverns and fissures in these rocks, but as a matter offact, the whole of the iron which they contain is in the state ofhydrated peroxide. This would indicate' that the iron has really beenderived from water percolating from above.Amongst the natural compounds of a metal, that with the greatestheat of formation should constitute the principal mineral of the parti-cular metal. If all minerals had been deposited from aqueonssolutions of tolerably simple composition, it would follow from thelaws of thermochemistry that there should only be one naturallyoccurring compound of each metal, but many minerals have bee31 .NEtiALOGIdAL CHEMISTRY. 37formed in very complex media and under extremely varied conditions,and these geological conditions have to be taken into account. Allminerals may, however, be broadly divided into the folloN-ing types :those which have been formed in an oxidising medium ; those whichhave been formed in a reducing medium; those which have beendeposited on a siliceous substratum; and those which have beendeposited on a calcareous substratum.The heats of formation of the more important manganese com-pounds are manganous sulphide, MnS, 22.6 cal. ; manganous oxide,AhO, 47.4 cal.; mnnganous carbonate, MIiC0.3, 54 9 cal.; andmanganese peroxide, MnOz, 58.1 cal.. These values are in completengrecment, with the fact that manganese peroxide is by far the mostabundniit mineral of manganese, that manganous sulphide is veryrare, whilst manganous oxide exists oiily in combination with theperoxide, and that manganous carbonate is a rare mineral, mainly.confined to veins and fissures, and existing only out of contact withoxygen. Tn all cases where the oxidation of the manganese is notcomplete this result is due to the non-permeable character of theminerals by which the manganese compound is surrounded.C. H. B.Cornpsition of Water from Uxiage (Isere), By E. PETJGOI!(J. Phurm. IS], 11, 241--245).-Berthier examined this water in 1823,and found the solid residue to be 5.76 grams per litre ; twenty p a r slater tllis became almost doubled in amount, and has smce remainedconstant. The following is the result of the author's analysis :-CaCO,. NaC1. KC1. CaSO,. N%S04. MgS04. N&.HAsO,.0.388 6.000 0.402 1.145 1.255 0.609 0 002SiOp H& Total.0.01 4 0.010 9822The total solid residue was 11.917 grams, the excess being due towater of crystallisation of the sulphates. The presence of minutetraces of iodine and boric acid was ascertained, the latter hasriug beenpreviously found by Dieulafait. Lefort has detected lithium,. rubi,dium, ferrous sulphide, sodium tkiosulpbate,. and organic matter.Sp. gr. 1.0084 ; dis.solved gases, nitrogen 19 c.c., carboriic anhydride,3.2 c.c., a t 0" and i60 mm, The other coiistituents agree closelywith those obtained by the auhhor. The probable origin of the wateris discussed. The water is accompanied by enormous yuantitiej ofgas, which is mainly composed of nitrogen and carbonic anhydride.J. T