28 ABSTRACTS OF CHEMICAL PAPERS. Mineralogical Chemistry. Fusibility of Minerals and their Solubility in Magmas. By CORNELIUS DOELTER (Chem. Centr., 1901, ii, 826-827 ; from Tsck. Min. Mitth., 1901, 20, 307-330). --The results are given of detailed obser- vations of the manner in which various minerals are attacked by molten magmas. As a rule, minerals with a very high melting point (quartz, corundum, olivine, leucite) are more sparingly soluble than those with a lower melting point (felspar, augite, mica), I n general, however, the soliibility of a mineralin a magma depends on the pressure, the temperature, and the chemical composition of the magma, as well as on the fusibility of the particular mineral. Retinite from Thessaly. By CONSTANTIN ZENGELIS (Chem. Centr., 1901, ii, 833; from l'sch.Min. Mitth., 1901, 20, 356).-This retinite is yellowish-red, almost opaque, hard and readily combustible, sp. gr. 1,0023. At 290°, it softens and fuses with decomposition. Benzene dissolves 17.4 per cent. The following analysis corresponds with that required for the formula C,,H,,O : L. J. 5. C. H. S. 0. Ash. Moisture. 78-47 9.23 0.39 10.616 1.4'7 0.214 L. 3. s. Calaverite. By SAMUEL L. PENFIELD and W. E. FORD (Amer. J. h'ci,, 1901, [iv], 12, 225-246. Compare Abstr., 1896, ii, 3l).-A detailed crystallographic account is given of crystals of calaverite from Cripple Creek, Colorado. They are interpreted as being monoclinic and elongated in the direction of the axis of symmetry, but the faces have very high indices and do not fall into zones.The axial ratios, a : b : c = 1.6313 : 1 : 1.1449, axial angle, p= S9'47$', and, twinning, resemble those of sylvanite, but calaverite differs from this mineral in having no distinct cleavage, The general formula (Au, Ag)'re, expresses the chemical composition of both calaverite and sylvanite, but the latter contains more silver, and its formula approximates to AuAgTe,. The following analyses are given of the material now described : All. Ag- Te. Gangue. Total. Sp. gr. 40.99 1.74 [57*25 0.02 100.00 9.328 42.77 0.40 l56.753 0.0s 100*00 9.388 The colour of the brightest calaverite crystals is silver-white, some- times with a yellowish cast ; i t is not bronze-yellow as often described. L. J. S. Monazite from New Granada. By NICHOLAS J. BLUMAN (Chem. News, 1901, 84, 175).-A sample of reddish-brown colour, sp.gr. 6.001 and hardness 5, gave the following numbers on analysis : Ce,O,. La,O,. Tho,. MnO. CaO, SnO,. P,O,. Fe,Zn,S. Total. 25.02 22.41 18.00 1.21 2.13 3-00 28.23 traces 100.00 D. A. L,MINEKALOGICAL CHEMISTRY. 29 Triplite from Moravia and its Decomposition Products. By FRANTIGEK KovAG and FR. SLAVIK (Julwb. &!fin., 1901, i, Ref., 354-356 ; from Vedh. geol. Reichsanst., 1900, 397-404. Compare Abstr., 1901, ii, 248).--Cleavage masses of triplite, more or less altered, occur in large nests in pegmatite at Wien and Cyrillhof in Moravia. The optical characters and the following analyses are given : I and I1 are of weathered material from Wien, sp. gr. 3.901 ; calculating the iron as ferrous, these agree with the usual formula, (R'ln,Pe,Mg),PO,(F,OH). I11 is of fairly fresh material and IV of much weathered material from Cyrillhof ; the latter decomposes hydrochloric acid with the liberation of much chlorine.Further alteration of the material results in the formation of a cellular mass of dufrenite and hydroxides of iron and manganese with a colourless hydrated phosphate of iron and manganese : analysis of this mixture gave VI. The dufrenite, separated as far as possible from the other substances, gave V, agreeing with the usual formula Fe,(OH),PO,. The insoluble residue is shown by analysis and micro- scopical examination to consist of quartz, felspar and muscovite. Fe,O, .............. FeO .................. I'ln,O, ............... MnO .................. A1,0, ...............CaO .................. Alkalis ............... MgO .................. P,O, .................. co, .................. H,O .................. P ....................... Insol. ............... I. 2.80 26.10 29.17 0.49 4.58 31.67 trace 4.1 6 1.1 1 0.84 - - - 11. 4-26 24.31 28.85 0.56 4.74 50.89 0.59 4.80 trace 0.35 - - - 111. 7.78 33.37 17-92 1.27 0.40 0.1 9 32.44 4.4s 0.S8 2.37 - - - I v. 37.0s 16.24 0.35 1.68 0-56 0.63 17.56 13 68 13.35 - -_ - - VI. 5-56 41.80 2-87 0.13 0.47 0.12 31.31 11.36 7.26 - - - -- ___ ------ Total (less 0 for F). 100.45 99.75 100.73 101.13 100.42 100*88 The first stage in the alteration of the triplite is the replacement of fluorine by hydroxyl with the formation of triploidite. This is then oxidised and decomposed with the separation of hydroxides of iron and manganese along cracks, and finally yields the mixture of dufrenite, &c, Near the nests of triplite, the quartz of the pegmatite is represented only by empty cavities, and it is suggested that this mineral has been removed by the fluorine set free on the alteration of the triplite.L. J. S. Emerald and Beryl from the Uralian Emerald Mines. By PETR A. ZEMJATSCHENSKY (Jahrb. Min., 1901, ii, Ref., 190-191; from Trav. Xoc. Nut. 8t. Petersburg, 1900, 29, l-l9).-The emerald mines on the Takowaja river, 85 versts north-east of Ekaterinburg, have, since 1832, yielded fair amounts of emerald, beryl, phenakite and alexandrite. The emeralds are embedded in a dark mica-schist, or30 ABSTBACTS OF CHEMICAL PAPERS. occur, intergrown with tourmaline and felspar, in masses of quartz and felspar in the mica-schist ; they are usually cloudy and enclose scales of mica, whilst along the frequent fractures felspar is deposited.The crystals have a zonal structure and are optically anomalous. Analyses 1-111 are of pale colour emerald, and IV-V of the dark brown mica in which they are embedded, Loss on SiO,. A1,03. Fe,03. BeO. MgO. K,O. Na,O. Mn,O,. ignition. Total. I. 66'65 18.43 trace 12.9 - - - - 2-19 100.17 11. 66.96 18.58 - 13.1 - - - - 2-1 100.74 111. 65-95 18.95 trace 12'89 - - - - 2'20 99'99 IV. 40.20 26.22 13.31 - 6'69 10'44 0.87 trace 1-81 99'55 V. 40.12 26'19 13'50 - 6.10 10.23 o a a o - 1-87 98'81 L. J. S. Minerals from the Ilmen Mountains. By P. SUSCHTSCHINSKY (Jahrb. Min., 1901, i, Ref., 361-363 ; ii, Ref., 205-206 ; from Trav.Xoc. Nat. Xt. Petersbui*g, 1900, 29, 21--46).-Minerals from the mchynite, aquamarine and zircon mines, near Miask, are described. .Aquamarine gave, on analysis, the results under I. Black, rhombic dodecahedra of garnet in mica-slate gave 11. Dark green crystals of Egirine-augite from druses in gneiss gave I11 (anal. by Antipoff). SiO,. A1,0,. Fe,O,. FeO. BeO. CaO. MgO. Na,O. H,O. Total. I. 66.02 18.81 - - 13.27 -- - - 1.45 99-55 99'96 111. 50'58 5'47 3-92 23-18 - 3.85 2-19 8.17 - 97.36 - - 11. 35.34 19-51 - 40.20 - 4.91 - L. J. S. Composition of Plagioclase. By W. TARASSENKO (Jahrb. Bin., 1901, ii, Ref., 180-189; from Mem. Nat. Soc. K&fl [Russ.], 1900, 16, 365-496. Compare Abstr., 1900, ii, 354).-The plagioclase of labra- dorite-rocks from (I) Selistsche (Gov.Volhynia) and (11) Gorodistsche (Gov. Kieff) was separated into several portions according to sp. gr. and each portion examined in detail. The eleven analyses, of which the means are given below, differ among themselves for each felspar only within the limits of errors of observation. The variation in the sp. gr. is attributed to the porosity of the material, due to the presence of fluid enclosures, cleavage cracks, &c. SiO,. A1,0,. CaO. Na,O. K,O. Sp. gr. Formula. I. 55.28 28.27 10.18 5.17 1.10 2-647-2.710 AblAnl 11. 53.05 29.77 12.08 4.30 0.80 2-697-2.756 Ab,An, It is concluded that the plagioclases are not isomorphous mixtures, but compounds of the albite and anorthite molecules in definite pro- portions. L. J. s. By FERRUCCIO ZAMBONINI (Jahyb.Min., 1901, ii, Ref., 19; from Riu. Min. Crist. Ital., 1900, 24, 13).-Small crystals of sodalite from an '' erratic block " at 5. Sisto, near Viterbo, gave, on analysis : Total (less SiO,. Al,O,. Fe,Os. Na,O. CaO, C1. H,O. OforC1). 36-60 34.26 1.85 17-75 0*90 4-31 5-14 99%4 Soddite from Viterbo. L. J. S.MINERALOGICAL CHEMISTRY. 31 [Amphibole in] Soda-syenite from Miask. By ARRIEN JOHNSEN (Jahrb. Min., 1901, ii, 117--127).-Descriptions are given of five rocks of the soda-syenite group from Miask in the Urals. One of these, called an segirine-augite-soda-syenite, consists of albite, a little micro- cline, aegirine-augite, and a peculiar amphibole. This amphibole is pleochroic and has a wide angle of optical extinction (c : c = 36') ; sp.gr. 3*15 ; an approximate analysis gave the following results : SiO,(+TiO,?). A1,0,. Fe203. FeO. MnO. MgO. CsO. 58.50 12.38 14.32 4.79 3.16 4.30 0.92 Na,O. K,O. Total. 4.09 0.48 102.94 It appears to be intermediate between riebeckite and glaucophane. L. J. S. Andalusite from the Rhaetian AJps. By AUGUST GRAMANN (Jahrb. Mirn., 1901, ii, Ref., 193-197; from separate publ. Zurich, 1899, 57 pp.).-At several localities in the Fluela and Scaletta districts in Switzerland, crystals of andalusite occur with cordierite, kyanite, sillimanite, muscovite, biotite, orthoclase, pmicline, &c., in quartz lenticles in biotite-gneiss, but not in the gneiss itself. The sp. gr. of the andalusite is lower than usual, being 3*0532-3*0829. The colour is peach-blossom-red or violet, and the crystals have sometimes a darker coloured kernel.The colouring matter appears to be TiO, (rutile) rather than Ti,O,. The extremes of five analyses are : SiO,. Al,03( + FeO). Fe203. H,O . 33.76-34'7 1 63.93-64.69 Nil-0.44 0*49-1*78 The alteration product of the andalusite is a white, scaly, sericitic material containing much quartz and carbonates. By the aggregation of numerous scales of this secondary sericite, large plates of muscovite are formed, analysis of which gave the following results, agreeing with those required for the formula 4H20,K,0,(Ca,Mg)0,6A1203, iOSi0, : SiO,. A1,0,. MgO. CaO. K,O. Na,O. H20. Total. 43.09 42.16 0.29 2-54 6.79 trace. 5.11 99.98 L. J. S. Fire-clay from Moravia. By FRANTISVEK Kov& and ANT. HA~KOVEC (Juhrb. Hin., 1901, ii, Ref., 226 ; from Zeit.chem. Ind. Prag, 1899,s pp.).-Beds of fire-clay occur in the Quader sandstone at Vranovd near Kunstadt. Analysis I .is of whitish, and 11, of dark greyish, more sandy, material. Loss on SiOz. TiO,. AI,O,. Fe,O,. CaO. MgO. Alkalis. SO,. ignition. Total, I. 52-42 tiace 33.56 1.17 0.77 0.38 1'28 - 10.84 100.42 [I. 52-11 0.17 27'73 5.92 0'91 0.57 1.07 0'21 12'78 100'47 L. J. 8.32 ABSTRACTS OF CHEMICAL PAPERS. Separation of Titaniferous Iron Ores in Basic Igneous Rocks By JOHAN H. L. VOGT (Chem. Centr., 1901, ii, 829 ; from Zeit. prakt. Geol., 1901, 289-296. Compare Abstr., 1900, ii, 63 ; 1901, ii, 319). -A graphic representation of analyses shows that as concentration takes place, a decrease in silica is accompanied by a decrease in alumina and alkalis and an increase in titanium and iron oxides, while the variations in the lime show no regularity.Very advanced stages in the differentiation cannot be explained by a simple addition or sub- traction of material, since, with varying conditions, the processes of differentiation are more or less changed as they proceed. In all prob- ability, the differentiation is effected by the transference of a dissolved constituent in a solvent ; the former being the bulk of the titanium and iron oxides and magnesia, and the latter a part of the silica with alumina, lime, and alkalis. The materials are concentrated in the same order in which they crystallise out from the magma, namely: (1) apatite ; (2) sulphides ; (3) titanium and iron oxides with spiuel ; (4) ferromsgnesian silicates. Cases are, however, lrnown in which all of these may be concentrated together. By GEORGE A. GOYDER (Trans. Roy. Xoc. South Aust~alia, 1901,25, 14).-This iron, of which the weight is 7+1bs., shows Widmanstatten figures and twin-lamellae (Neumann lines) on the etched surface and consists of blades of kamacite with L. J. S. A South Australian Meteorite. I thin plates of taenite and grains of troilite. Analysis by Chapman gave : Fe. Ni. co. S. P. Insol. Total. 88.85 9.07 0.34 0.75 0.27 0.03 99.31 L. w. s. Sp. gr. 7-693 J. 8. Analysis of the Sulphurous Waters of Vernet-les-Bains. By LBON PERRER (J. Phamz. Chim., 1901, [vi], 14, 385-389).-l'he waters of Vernet-les-Bains belong to the class of thermal sulphuretted alkaline waters. Complete analyses of samples from seven different springs are given in t h e paper. H. R. LE 8.