MINERALOGlCAL CHEMISTRY. M i n e r a l o g i c a l C h e m i s t r y . 95 Rock Salt from Saltville. Ry B. E. SLOAN (Chenz. News, 40, 187).-Some specimens of dark brownish-red rock salt obtained from the salt wells a t Saltville, Washington Co., Virginia, gnve the follow- ing results on analysis :- NaC1. KC1. CaS04.2H20. Fe,O,. SiOz. 89.2 1 trace 4-86 0.84 4.53 The presence of strontium, barium, OP lithium could not be de- tected. L. T. 0’s. Livingstonite. By F. P. VENABLES (Chem. News, 40, 186--187).- Owing to doubts as to the purity of the samples of this mineral analysed by BBrcena, and consequently as to the accuracy of the formula assigned to it by him, the author has a t his request examined purer specimens, and the numbers obtained give t,he formula HgS.2Sb,S3 instead of 4Sb,S3 + HgS + FeS2.Calcium sulphatc mas present in considerable quantities, but as it occurs only as a matrix, it may be eliminated from the results of analysis. This is the most strongly acid sulphantimonite yet known. Magnetite. By E. C. SMITH (Chern. ATews, 40, 189).--This mineral occurs in Henry Co., Virginia, in loose crystals coated wit,h ferric oxide, which can easily be washed off, when they present the ordinary black colour and general appearance of magnetic iron ore. Hardness = 6 ; sp. *gr. 4.98. The crystals are strongly magnetic, and are curiously distorted on the surface by step-like projections and depressions, giving them the appearance of rhornbic octohedrons, but with irregularly varying inclinations of the general surfaces. The analysis of the cleansed crystals show them.t o consist of pure mag- netite. L. T. 0’s. L. T. 0’s.96 ABSTRACTS OF CHEMICAL PAPERS. Crystalline Form of Sardinian Anglesite. By Q. SET,T,A (Gazzetfcr,, 9, 344-353b.-Anglesite7 which is found so frequently and in such fine crystals in the mines of Monteponi and elsewhere in t,he island of Sardinia, formed the subject of a monograph by Lang, and since then this mineral has been studied by other crystallographers, espcciallp Hessenbcrg, Zepharowich, and Kreuner. Although the number of forms already described is considerable, a table of no less t)han 44 being given in the paper, a careful examination of numerous fine crystals has enabled the author to increase it greatly. DetaJls of the measurements of 38 specimens are given, b u t many of these symbols cannot be considered as definitely established until they have been carefully compared with the results of former workers in this field. I n the second part of the memoir the aukhor proposes to discuss the relation between the different forms and the size of the crystals, as well as to give descriptions of other forms of angleqite.C. E. G. Composition of Amblygonite. By S. L. PENFIELD (CAem. News, 40, 208--20!~).-Brush and Dana (Am. JOUY. Sci. [3], 16, 42) have shown that triploidite, (Mn,Fe) 3Pz08 + (Mn,Fe)( OH),, is isomor- phous with wagnerite, hIgJ’,O, + I\IgF2, and similar in composition to triplite, (Mn,Pe)3P208 + (ililn,Fe)F,, and consequently argue that the OH-group plays the same part in triploidite as fluorine does in the other two minerals. Ir, amhlypnite the author shows that hydroxyl and fluol-ine are also isornorphous. The results of the analyses give the ratios of P : A1 : (Li,Na) : (OH,F) = 1 : 1 : 1 : 1, corresponding with the formula A1,P20, +2(Li,Na) (OH,F), or- 381,P,O, AL(OH,F)t3 S(Li,Na),POi + { 2 (Li,Na) (OH,F) Owing to a difference in the optical properties of some specimens, Des Cloizeaux separates the mineral into two varieties, but the varia- tion is so slight as hardly t o afford sufficient ground for the dis- tinc ti on.Details of the method of analysis are given. Uranium Minerals from North Carolina. L. T. 0’s. Ey F. A. GENTH (Cjbeqn. News, 40, 210--212).-These minerals, fonlrd in the Flat Rock Mine, Mitchell Co., North Carolina, are as follows :- UranotiZ occui-s as a pale yellow coating on gummite, and is amor- phous, massive, and compact.Hardness = 2.5 ; sp. gr. 3.84 ; lustre dull. In colour it varies from a straw-yellow t o lemon-yellow ; its streak is of a pale straw yellow, it is opaque, and has an uneven fracture. The analysis agrees with the formula Ca3( 0,),Si6O2,.18H,O, rather than Ca3( Oz),Si5O,,.l5H2O given by Rammelsberg. Guwm&e.-This orange-coloured knineral occurs in compact, amor- phous, nodular masses. Hardness 3 ; sp. gr. 4.84; lustre resinous ; and streak orange-yellow. It is opaque, and has it subcoochoidal fracture. It is soluble in acetic acid. Various opinions have been held concerning the constitution of this mineral, and the a,nthor, with Patera, mainhiins that it is principally lead uranate.Gummite is the result of the alteration of uraniiiite, and that fromMINERALOGICAL CHEMISTRY. 97 North Carolina is a mechanical mixture, since uranotil penetrates the mass throughout. From the author’s analyses it is found to consist of- Uranium hydrate, H2(UO2)O2 + H,O .... 40.10 per centa Uranotil, Cat(U02)6Si6021 + 18H20 .... 33.38 ,, Lead uranate, Pb(U02)203 + 6ILO.. . . . . 22.66 ,, Barium uranate, Ba(U02)203 + 6H20.. . . 4.26 ,, Gummite from Johann Georgenstadt has probably the follomirrg composition calculatea from Kersten’s analyses :- Uranium hydrate, H2(U02)02 + H20.. . . Uranotil, Ch(U02)qSi6021 + 18H20 . . . . 30.54 .. Phosphuranylite, (U02)3P208 + 6H20.. . . 8.73 .. Calcium uranate, Ca,(UO,),O, f 6H20 . . 52-99 ), 6.32 per cent. Phosyhurany 7ite exhibits under the microscope rectangular pcnrly The analysis shows that it may scales, having a deep brown colour. be expressed by 5: formula similar t o that of troegerite.Phosphuranylite = (U02)3P208 + 6H20 Troegerite . . . . = (U02)3A~208 + 12H,O The analyses of pittinite and eliasite admit of no calculation, as they appear bo contain too many foreign substances. A saniple supposed to be uranite was found to contain lime and’not a trace of copper, and therefore consists of aufunite. L. T. 0’s. By N. PELLEGRINI (G17Z- zetta,* 9, 293).-This specimen of chrysocolla, from Cerro Blanco in Chili, was bright green on the outside, farther in it was a beautif111 deep green, and in the centre a dark greenish-blue approaching t o brown. These were mechanically separated and analysed :- Outside.Second layer. Centre. H,O.. . . . . . . . . 7.296 24-007 26.1 48 SiO,. . . . . . . . . . 16.621 26.685 95.938 CUO.. . . . . . . . . 63.306 39.891 31.913 Analyses of Chryaocolla from Chili. . . . . . . 4.957 { +:::!!} 9.227 FeO . . . . . . . . . . - 1.824 - CaO.. . . . . . . . . 3.081 2.307 3.992 Loss.. . . . . . . . . 2.739 0.372 2.782 100*000 100*000 100~000 - -. L__ C. E. G. Volcanic Ash from Cotopaxi. By J. R. SANTOS (Chem. New.?, 40, 186).-This ash, which fell during a recent eruption at Bahia de Caraguez, a distance of 120 miles from Cotopaxi, consisted of a fine brown powder containing glassy granules mixed with ferric oxide. Its specific gravity = 2.743 and its analysis gave- * The Qazzetta chimica italiana will in future be abbreviated to Qazzetta.+ This is perhaps 3*415.-C. E. G. TOL. XXXVIII. F,98 ABSTRACTS OF CHEMICAL PAPERS. SiO,. A120,. Peso3. PbO. CaO. MgO. 56.661 19.398 7.523 0.575 6.229 trace 6.123 2.425 0.8G2 NtlaO. K20. 8 2 0 . Discarding the iron and water, the above numbers lead to tlic for- The quantity of lead contained in this mula (K,Na,CaPb)A1,Si501~. ash is interesting, as is also its state of combination, namely, silicate. L. T. 0’s.MINERALOGlCAL CHEMISTRY.M i n e r a l o g i c a l C h e m i s t r y .95Rock Salt from Saltville. Ry B. E. SLOAN (Chenz. News, 40,187).-Some specimens of dark brownish-red rock salt obtained fromthe salt wells a t Saltville, Washington Co., Virginia, gnve the follow-ing results on analysis :-NaC1. KC1. CaS04.2H20.Fe,O,. SiOz.89.2 1 trace 4-86 0.84 4.53The presence of strontium, barium, OP lithium could not be de-tected. L. T. 0’s.Livingstonite. By F. P. VENABLES (Chem. News, 40, 186--187).-Owing to doubts as to the purity of the samples of this mineralanalysed by BBrcena, and consequently as to the accuracy of the formulaassigned to it by him, the author has a t his request examined purerspecimens, and the numbers obtained give t,he formula HgS.2Sb,S3instead of 4Sb,S3 + HgS + FeS2. Calcium sulphatc mas present inconsiderable quantities, but as it occurs only as a matrix, it may beeliminated from the results of analysis. This is the most stronglyacid sulphantimonite yet known.Magnetite. By E. C. SMITH (Chern. ATews, 40, 189).--Thismineral occurs in Henry Co., Virginia, in loose crystals coated wit,hferric oxide, which can easily be washed off, when they present theordinary black colour and general appearance of magnetic iron ore.Hardness = 6 ; sp.*gr. 4.98. The crystals are strongly magnetic,and are curiously distorted on the surface by step-like projectionsand depressions, giving them the appearance of rhornbic octohedrons,but with irregularly varying inclinations of the general surfaces. Theanalysis of the cleansed crystals show them. t o consist of pure mag-netite. L. T. 0’s.L. T. 0’s96 ABSTRACTS OF CHEMICAL PAPERS.Crystalline Form of Sardinian Anglesite. By Q. SET,T,A(Gazzetfcr,, 9, 344-353b.-Anglesite7 which is found so frequently andin such fine crystals in the mines of Monteponi and elsewhere in t,heisland of Sardinia, formed the subject of a monograph by Lang, andsince then this mineral has been studied by other crystallographers,espcciallp Hessenbcrg, Zepharowich, and Kreuner.Although thenumber of forms already described is considerable, a table of no lesst)han 44 being given in the paper, a careful examination of numerousfine crystals has enabled the author to increase it greatly. DetaJls ofthe measurements of 38 specimens are given, b u t many of thesesymbols cannot be considered as definitely established until theyhave been carefully compared with the results of former workers inthis field. I n the second part of the memoir the aukhor proposes todiscuss the relation between the different forms and the size of thecrystals, as well as to give descriptions of other forms of angleqite.C.E. G.Composition of Amblygonite. By S. L. PENFIELD (CAem.News, 40, 208--20!~).-Brush and Dana (Am. JOUY. Sci. [3], 16, 42)have shown that triploidite, (Mn,Fe) 3Pz08 + (Mn,Fe)( OH),, is isomor-phous with wagnerite, hIgJ’,O, + I\IgF2, and similar in compositionto triplite, (Mn,Pe)3P208 + (ililn,Fe)F,, and consequently argue that theOH-group plays the same part in triploidite as fluorine does in theother two minerals. Ir, amhlypnite the author shows that hydroxyland fluol-ine are also isornorphous. The results of the analyses givethe ratios of P : A1 : (Li,Na) : (OH,F) = 1 : 1 : 1 : 1, correspondingwith the formula A1,P20, +2(Li,Na) (OH,F), or-381,P,O, AL(OH,F)t3S(Li,Na),POi + { 2 (Li,Na) (OH,F)Owing to a difference in the optical properties of some specimens,Des Cloizeaux separates the mineral into two varieties, but the varia-tion is so slight as hardly t o afford sufficient ground for the dis-tinc ti on.Details of the method of analysis are given.Uranium Minerals from North Carolina.L.T. 0’s.Ey F. A. GENTH(Cjbeqn. News, 40, 210--212).-These minerals, fonlrd in the FlatRock Mine, Mitchell Co., North Carolina, are as follows :-UranotiZ occui-s as a pale yellow coating on gummite, and is amor-phous, massive, and compact. Hardness = 2.5 ; sp. gr. 3.84 ; lustredull. In colour it varies from a straw-yellow t o lemon-yellow ; itsstreak is of a pale straw yellow, it is opaque, and has an uneven fracture.The analysis agrees with the formula Ca3( 0,),Si6O2,.18H,O, ratherthan Ca3( Oz),Si5O,,.l5H2O given by Rammelsberg.Guwm&e.-This orange-coloured knineral occurs in compact, amor-phous, nodular masses.Hardness 3 ; sp. gr. 4.84; lustre resinous ;and streak orange-yellow. It is opaque, and has it subcoochoidalfracture. It is soluble in acetic acid. Various opinions havebeen held concerning the constitution of this mineral, and thea,nthor, with Patera, mainhiins that it is principally lead uranate.Gummite is the result of the alteration of uraniiiite, and that froMINERALOGICAL CHEMISTRY. 97North Carolina is a mechanical mixture, since uranotil penetrates themass throughout. From the author’s analyses it is found to consistof-Uranium hydrate, H2(UO2)O2 + H,O ....40.10 per centaUranotil, Cat(U02)6Si6021 + 18H20 .... 33.38 ,,Lead uranate, Pb(U02)203 + 6ILO.. . . . . 22.66 ,,Barium uranate, Ba(U02)203 + 6H20.. . . 4.26 ,,Gummite from Johann Georgenstadt has probably the follomirrgcomposition calculatea from Kersten’s analyses :-Uranium hydrate, H2(U02)02 + H20.. . .Uranotil, Ch(U02)qSi6021 + 18H20 . . . . 30.54 .. Phosphuranylite, (U02)3P208 + 6H20.. . . 8.73 .. Calcium uranate, Ca,(UO,),O, f 6H20 . . 52-99 ),6.32 per cent.Phosyhurany 7ite exhibits under the microscope rectangular pcnrlyThe analysis shows that it may scales, having a deep brown colour.be expressed by 5: formula similar t o that of troegerite.Phosphuranylite = (U02)3P208 + 6H20Troegerite .. . . = (U02)3A~208 + 12H,OThe analyses of pittinite and eliasite admit of no calculation, as theyappear bo contain too many foreign substances. A saniple supposedto be uranite was found to contain lime and’not a trace of copper, andtherefore consists of aufunite. L. T. 0’s.By N. PELLEGRINI (G17Z-zetta,* 9, 293).-This specimen of chrysocolla, from Cerro Blanco inChili, was bright green on the outside, farther in it was a beautif111deep green, and in the centre a dark greenish-blue approaching t obrown. These were mechanically separated and analysed :-Outside. Second layer. Centre.H,O.. . . . . . . . . 7.296 24-007 26.1 48SiO,. . . . . . . . . . 16.621 26.685 95.938CUO.. . . . . . . . . 63.306 39.891 31.913Analyses of Chryaocolla from Chili.. . . . . . 4.957 { +:::!!} 9.227FeO . . . . . . . . . . - 1.824 -CaO.. . . . . . . . . 3.081 2.307 3.992Loss.. . . . . . . . . 2.739 0.372 2.782100*000 100*000 100~000- -. L__C. E. G.Volcanic Ash from Cotopaxi. By J. R. SANTOS (Chem. New.?,40, 186).-This ash, which fell during a recent eruption at Bahia deCaraguez, a distance of 120 miles from Cotopaxi, consisted of a finebrown powder containing glassy granules mixed with ferric oxide.Its specific gravity = 2.743 and its analysis gave-* The Qazzetta chimica italiana will in future be abbreviated to Qazzetta. + This is perhaps 3*415.-C. E. G.TOL. XXXVIII. F98 ABSTRACTS OF CHEMICAL PAPERS.SiO,. A120,. Peso3. PbO. CaO. MgO.56.661 19.398 7.523 0.575 6.229 trace6.123 2.425 0.8G2NtlaO. K20. 8 2 0 .Discarding the iron and water, the above numbers lead to tlic for-The quantity of lead contained in this mula (K,Na,CaPb)A1,Si501~.ash is interesting, as is also its state of combination, namely, silicate.L. T. 0’s