MINERALOGICAL CHENISTRY. M i n e r a l o g i c a1 Chemistry. 123 Boleite, a New Mineral. By MALLARD and E. CUMENGE (Coinpt. renid., 113, 5 19--524).-This mineral occurs in cubical crystals of a fine indigo-blue colour in an argillaceous matrix, termed jctboncillo, next above the true copper-bearing bed of Boleo, near Santa Rosalia, Lower California. The crystals are accompanied by anglesite, phosgenite, cerussite, and atacamite. They are not decom, posed by water ; they melt in a candle flame, and, when heated in a closed tube, decompose with evolution of water. Two analyses of clean samples yield the numbers :- a I. 11. Calculated. Silver ........... 8.85 8.70 8.50 Lead.. .......... 48.45 49.75 48.90 Chlorine ........ 19.98 19.00 19.55 Water. .......... 4.77 4-00 4.28 Copper.......... 13.95 14-50 15.00 Oxygen (by diff.) . 4.00 4.05 3.77 The calculated percentages correspond with the formula 3[PbCl*OH,CuC1-OH] + AgC1. Metallic copper is obtained by re- duction in a current of dry hydrogen without the liberation of hydro- chloric acid: this would seem to indicate that the chlorine is not combined with t,he copper, but, in reality, the hydrochloric acid formed immediateiy reacts on the lead oxychloride, producing lead chloride and water. The formula given best shows the relationships of this mineral to laurionite, PbC1-OH, and atacamite, CuCl*OH,Cu( OH),. Brooke’s percylite, from Sonora, may possibly be the same mineral, although it,s imperfect analyses do not indicate the presence of silver. I n hardness, the mineral is a little superior to calcite, and its density is 5.08.The common form is the cube without modifying faces. Some crystals show very sharp and brilliant octahedral faces ; more rarely, dodecahedra1 faces are met with. Some small crystals have been observed with the edges replaced by re-entering angles formed by faces of the hexakistetrahedron. The cleavage is distinct and easy, parallel to the faces of the cube, the octahedral cleavage being less distinct. The observed optical properties are those of very birefringent, negative, uniaxial crystals ; the index of refraction could not be accurately determined; for a, prism formed by the cubical and dodecahedral faces, its approximate value is 2.07. Bol6ite belongs to the tetragonal system, though pseudo-cubic in habit. Along with the cubical crystals, octahedral crystals occur in pecu- liar groupings, showing the octahedml faces brilliant, but generally formed of three facettes, composing a low pyramid.k 2124 ABSTRACTS OF CHEMICAL PAPERS. The angular measurements are dificult, aud only yield approxi- mately the values f o r the parameters, a : c = 1 : 1.645. The com- position of the octahedral crystals is the same as that of the cubical crystals :- Silver ........ 9.2 9.4 8-5 Copper.. ..... 14.8 L5.0 15.0 Lead. ........ 50.2 50.7 48.9 Chlorine.. .... 19.4 19.7 19.5 Cubic cryst. Octahedral cryst. Calculated. Their densities appear to be about t,he same, a small specimeu of the octahedral crystals giving 5.0. W. T. Polydymite, Ullmannite, and Wolfsbergite. By H. L-4SPEI’RES (Zeit.Kryst. Min., 19, 417-436).;1. Po1ydymite.-The author brings forward fresh evidence in support of the formula Ni,S, he pro- pounded 15 years ago for polydgmite and nickel-bismuth glance, minerals which he regards as identical. The accuracy of this formula is confirmed by the a,nalysis of the polydymite from Sudburj, in Canada, as well as by the examination of some excellent crystals of this mineral from the Griineau mine, in the Siegen district. 2. UZEmannite.-The author describes some crystals of ullmannite, from the Landeskrone mine, near Siegen. Although this mineral is of frequent occurrence in the Siege11 mines, it has never before been found in crystals. 3. Wolfsbergite.-Of the crystalline form of the copper-antimony glance (Wolfsbergite), from Wolfsberg, in the Harz, all that is known is the brief account given by G.Rose in 1835. A discovery of a well-crystallised specimen in the Bonn Museum has enabled the author to give a detailed description of the crystallography of this mineral. The forms he has observed are:-OP, +Pw, Pm, 2 P a , pm, ;-Pa, QP+, ;P3. The axial ratio is cc : b : c = 0.52830 : 1 : 1.62339. B. H. B. Some New Chilian Minerals : Darapskite, Lautarite, Iodo- chromate. By A. DIETZE (Zeit. Kryst. &Fin., 19, 445-451).- 1. Darapskite.-This is the name given by the author to a new double salt of the cornposition repyesented by the formula NaNO, + Na,SO, + H,O. It is colourless, transparent, and occurs in square tablets bevelled by tetragonal pyramids. The new mineral is found at the Pampa del Toro, and is named after Dr.L. Darapsky, the well-known mineralogist, of Santiago. 2. I;autarite.-Although it has long been known that the iodine contained in the caliche or raw nitrate is due to the presence of iodates, no iodate has hitherto been found as a distinct mineral species. The new mineral described by the author is calcium iodate, the analytical results being in accord with the formula Ca(IO&. It occurs at the “ Pampa del Pique III?” in the form of large, monoclinic prisms, having the sp. p. of 4.59. I t is transparent, and of a yellow- ish colour. 3. Iodochromate.--Near the chief locality of lauterite, small, yellow It is very slightly soluble in water,YINERALOQICAL OHEMISTRY. 125 crystals occur in the caliche. These prove on analysis to be a double iodate and chromate of calcium, of the formula 7Ca(IO&,8CaCrOa.The accuracy of this formula is shown by the results of seven analyses. B. H. B. Formula of Axinite. By A. KENNGOTT (Jahrb. f. illin., 1891, ii, Mem. 335--336).-1n a recent paper (Abstr., 1891,1168), the author published a formula for axinite calculated from two analyses given by Whihefield. This result he now compares with three analyses given by 3'. A . Genth (Amer. J. Xci., 41, 394). These analyses refer to axinite from Franklin, New Jersey, in crystals and in lamelle, and from Guadalcazar, in Mexico. The analyses of axinite from Franklin give results closely approaching those obtained from White- field's analyses. The axinite from Guadalcazar, however, wag appa- rently admixed with white felspar partially converted into kaolin, and, consequently, cannot be considered suficiently pure to serve as the basis for the calculation of a formula.B. H. B. Constitution of certain Micas, Vermiculites, and Chlorites. By F. W. CLARKE and E. A. SCHKEIDER (dnzer. J. Xci., 42,242-251). -In a previous paper (Abstr., 1891, 529), the authors considered the constitution of the mica and chlorite groups. The present paper is a continuation of the same research. Throughout the investigation the fundamental hypothesis that the minerals studied are substitution derivatives of normal salts has been amply justified. Of the so-called vermiculites, two only, jefferisite and kerrite, were considered in the former paper, and these wcre shown to be tri- hydrated micas in which the original alkalis had been replaced by hydrogen. The examination of other varieties shows that kerrite is essentially a t,rihydrated hydrophlogopite.Protovermiculite, from Magnet Cove, Arkansas, is the same substance mixed with an equal proportion of trihydrated hydroclintonite. Jeff erisite is a similar mixture of hydrobiotite and hydroclintonite, also trihydrated. An altered biotite, from Henderson Co., North Carolina? is found to be essentially a biotite, about half way changed into a. vermiculite, and is interesting as a transition product. All the vermiculites are not so simple as the above-named minerals. I n some members of the group, there seems to be a small admixture of chloritic molecules, and it is even probable that many interme6iate stages between mica and chlorite may exist.As bearing on this question, the authors give analyses of the ballite from Nottingham, Chester Go., Pennsyl- vania, and of the vermicixlites from Lennie, Delaware Go., Pennsyl- vania. They also give the results of their examination of vermiculites from Newlin, Chester Go., and from Middletown, Delaware Co., in both of which Tschermak's view, that some of the vermiculites are probably chlorites, is partly sustained. A very interesting example of the way in which the chloritic vermiculites approach the serpen- tines in composition has been furnished by a specimen found at Old Wolf Quarry, Chestnut Hill, Easton, Pennsylvania, an analysis of which is given by the authors. Lastly, there is one other mineral examined during this investigation, a pale, yellowish-green mica, from126 ABSTRAOTS OF OHEMIOAL PAPERS.Aubum, Maine, where it occurs in direct contact with ordinary mus- covite. Analysis shows that it has the composition of muscovite, The case is interesting as showing a secondary growth of muscovite on muscovite, with a marked difference in outward appearance between the two formations. 13. H. B. Genesis of Iron Ores by Replacement of Limestone. By J. P. KIMRALL (dmer. J. Xci., 42, 231-241).-The object of this memoir is to show that the well-recognised products of epigenesis, like siderite and ferrocalcite, are, as a rule, also products of direct psendomorphous replacement of isomorphous calcium carbonate. From this it follows that secondary o r indirect replacement of calcium aarbonate by ferric hydroxide is wrought through alteration of pseudo- morphons siderite or ferrocalcite, and also, through progressive alteration, by ferric oxide and even by magnetic oxide.As the result of his investigations, the author advances the proposition that de- posits of concentrated iron ores occur far more extensively a s pseudo- morphons replacements than has hitherto been made to appeal., and far more extensively than by original sedimentation of ferric hydr- oxide. B. H. B. The Basalt of the Stempel, near Marburg. By M. BAUER (Jahrb. f. Min., 1891, ii, Mem. 2:31-271).-This is the concluding instalment of an elaborate monograph (compare Abstr., 1891, 1440) on the basalt occurring at the hill known as the Stempel, which rises above the sandstone of the Lahn plateau.This section deals with the inclusions met with in the rock. These inclusions consist of limestone, quartz, apatite, nepheline, felspar, amphibolite, titanite, and zircon. 13. H. B.MINERALOGICAL CHENISTRY.M i n e r a l o g i c a1 Chemistry.123Boleite, a New Mineral. By MALLARD and E. CUMENGE(Coinpt. renid., 113, 5 19--524).-This mineral occurs in cubicalcrystals of a fine indigo-blue colour in an argillaceous matrix, termedjctboncillo, next above the true copper-bearing bed of Boleo, nearSanta Rosalia, Lower California. The crystals are accompanied byanglesite, phosgenite, cerussite, and atacamite. They are not decom,posed by water ; they melt in a candle flame, and, when heated in aclosed tube, decompose with evolution of water.Two analyses of clean samples yield the numbers :-aI.11. Calculated.Silver ........... 8.85 8.70 8.50Lead.. .......... 48.45 49.75 48.90Chlorine ........ 19.98 19.00 19.55Water. .......... 4.77 4-00 4.28Copper. ......... 13.95 14-50 15.00Oxygen (by diff.) . 4.00 4.05 3.77The calculated percentages correspond with the formula3[PbCl*OH,CuC1-OH] + AgC1. Metallic copper is obtained by re-duction in a current of dry hydrogen without the liberation of hydro-chloric acid: this would seem to indicate that the chlorine is notcombined with t,he copper, but, in reality, the hydrochloric acidformed immediateiy reacts on the lead oxychloride, producing leadchloride and water. The formula given best shows the relationshipsof this mineral to laurionite, PbC1-OH, and atacamite,CuCl*OH,Cu( OH),.Brooke’s percylite, from Sonora, may possibly be the same mineral,although it,s imperfect analyses do not indicate the presence of silver.I n hardness, the mineral is a little superior to calcite, and itsdensity is 5.08.The common form is the cube without modifyingfaces. Some crystals show very sharp and brilliant octahedral faces ;more rarely, dodecahedra1 faces are met with. Some small crystalshave been observed with the edges replaced by re-entering anglesformed by faces of the hexakistetrahedron. The cleavage is distinctand easy, parallel to the faces of the cube, the octahedral cleavagebeing less distinct. The observed optical properties are those ofvery birefringent, negative, uniaxial crystals ; the index of refractioncould not be accurately determined; for a, prism formed by thecubical and dodecahedral faces, its approximate value is 2.07.Bol6itebelongs to the tetragonal system, though pseudo-cubic in habit.Along with the cubical crystals, octahedral crystals occur in pecu-liar groupings, showing the octahedml faces brilliant, but generallyformed of three facettes, composing a low pyramid.k 124 ABSTRACTS OF CHEMICAL PAPERS.The angular measurements are dificult, aud only yield approxi-mately the values f o r the parameters, a : c = 1 : 1.645. The com-position of the octahedral crystals is the same as that of the cubicalcrystals :-Silver ........ 9.2 9.4 8-5Copper.. ..... 14.8 L5.0 15.0Lead. ........50.2 50.7 48.9Chlorine.. .... 19.4 19.7 19.5Cubic cryst. Octahedral cryst. Calculated.Their densities appear to be about t,he same, a small specimeu ofthe octahedral crystals giving 5.0. W. T.Polydymite, Ullmannite, and Wolfsbergite. By H. L-4SPEI’RES(Zeit. Kryst. Min., 19, 417-436).;1. Po1ydymite.-The authorbrings forward fresh evidence in support of the formula Ni,S, he pro-pounded 15 years ago for polydgmite and nickel-bismuth glance,minerals which he regards as identical. The accuracy of this formulais confirmed by the a,nalysis of the polydymite from Sudburj, inCanada, as well as by the examination of some excellent crystals ofthis mineral from the Griineau mine, in the Siegen district.2. UZEmannite.-The author describes some crystals of ullmannite,from the Landeskrone mine, near Siegen.Although this mineral isof frequent occurrence in the Siege11 mines, it has never before beenfound in crystals.3. Wolfsbergite.-Of the crystalline form of the copper-antimonyglance (Wolfsbergite), from Wolfsberg, in the Harz, all that is knownis the brief account given by G. Rose in 1835. A discovery of awell-crystallised specimen in the Bonn Museum has enabled theauthor to give a detailed description of the crystallography of thismineral. The forms he has observed are:-OP, +Pw, Pm, 2 P a ,pm, ;-Pa, QP+, ;P3. The axial ratio is cc : b : c = 0.52830 : 1 : 1.62339.B. H. B.Some New Chilian Minerals : Darapskite, Lautarite, Iodo-chromate. By A. DIETZE (Zeit. Kryst. &Fin., 19, 445-451).-1.Darapskite.-This is the name given by the author to a new doublesalt of the cornposition repyesented by the formula NaNO, + Na,SO,+ H,O. It is colourless, transparent, and occurs in square tabletsbevelled by tetragonal pyramids. The new mineral is found at thePampa del Toro, and is named after Dr. L. Darapsky, the well-knownmineralogist, of Santiago.2. I;autarite.-Although it has long been known that the iodinecontained in the caliche or raw nitrate is due to the presence ofiodates, no iodate has hitherto been found as a distinct mineral species.The new mineral described by the author is calcium iodate, theanalytical results being in accord with the formula Ca(IO&. Itoccurs at the “ Pampa del Pique III?” in the form of large, monoclinicprisms, having the sp.p. of 4.59. I t is transparent, and of a yellow-ish colour.3. Iodochromate.--Near the chief locality of lauterite, small, yellowIt is very slightly soluble in waterYINERALOQICAL OHEMISTRY. 125crystals occur in the caliche. These prove on analysis to be a doubleiodate and chromate of calcium, of the formula 7Ca(IO&,8CaCrOa.The accuracy of this formula is shown by the results of sevenanalyses. B. H. B.Formula of Axinite. By A. KENNGOTT (Jahrb. f. illin., 1891, ii,Mem. 335--336).-1n a recent paper (Abstr., 1891,1168), the authorpublished a formula for axinite calculated from two analyses givenby Whihefield. This result he now compares with three analysesgiven by 3'. A . Genth (Amer. J. Xci., 41, 394). These analyses referto axinite from Franklin, New Jersey, in crystals and in lamelle,and from Guadalcazar, in Mexico.The analyses of axinite fromFranklin give results closely approaching those obtained from White-field's analyses. The axinite from Guadalcazar, however, wag appa-rently admixed with white felspar partially converted into kaolin,and, consequently, cannot be considered suficiently pure to serve asthe basis for the calculation of a formula. B. H. B.Constitution of certain Micas, Vermiculites, and Chlorites.By F. W. CLARKE and E. A. SCHKEIDER (dnzer. J. Xci., 42,242-251).-In a previous paper (Abstr., 1891, 529), the authors considered theconstitution of the mica and chlorite groups. The present paper is acontinuation of the same research.Throughout the investigationthe fundamental hypothesis that the minerals studied are substitutionderivatives of normal salts has been amply justified.Of the so-called vermiculites, two only, jefferisite and kerrite, wereconsidered in the former paper, and these wcre shown to be tri-hydrated micas in which the original alkalis had been replaced byhydrogen. The examination of other varieties shows that kerrite isessentially a t,rihydrated hydrophlogopite. Protovermiculite, fromMagnet Cove, Arkansas, is the same substance mixed with an equalproportion of trihydrated hydroclintonite. Jeff erisite is a similarmixture of hydrobiotite and hydroclintonite, also trihydrated. Analtered biotite, from Henderson Co., North Carolina? is found to beessentially a biotite, about half way changed into a.vermiculite, andis interesting as a transition product. All the vermiculites are notso simple as the above-named minerals. I n some members of thegroup, there seems to be a small admixture of chloritic molecules,and it is even probable that many interme6iate stages between micaand chlorite may exist. As bearing on this question, the authorsgive analyses of the ballite from Nottingham, Chester Go., Pennsyl-vania, and of the vermicixlites from Lennie, Delaware Go., Pennsyl-vania. They also give the results of their examination of vermiculitesfrom Newlin, Chester Go., and from Middletown, Delaware Co., inboth of which Tschermak's view, that some of the vermiculites areprobably chlorites, is partly sustained.A very interesting exampleof the way in which the chloritic vermiculites approach the serpen-tines in composition has been furnished by a specimen found at OldWolf Quarry, Chestnut Hill, Easton, Pennsylvania, an analysis ofwhich is given by the authors. Lastly, there is one other mineralexamined during this investigation, a pale, yellowish-green mica, fro126 ABSTRAOTS OF OHEMIOAL PAPERS.Aubum, Maine, where it occurs in direct contact with ordinary mus-covite. Analysis shows that it has the composition of muscovite,The case is interesting as showing a secondary growth of muscoviteon muscovite, with a marked difference in outward appearancebetween the two formations. 13. H. B.Genesis of Iron Ores by Replacement of Limestone. ByJ. P. KIMRALL (dmer. J. Xci., 42, 231-241).-The object of thismemoir is to show that the well-recognised products of epigenesis,like siderite and ferrocalcite, are, as a rule, also products of directpsendomorphous replacement of isomorphous calcium carbonate.From this it follows that secondary o r indirect replacement of calciumaarbonate by ferric hydroxide is wrought through alteration of pseudo-morphons siderite or ferrocalcite, and also, through progressivealteration, by ferric oxide and even by magnetic oxide. As the resultof his investigations, the author advances the proposition that de-posits of concentrated iron ores occur far more extensively a s pseudo-morphons replacements than has hitherto been made to appeal., andfar more extensively than by original sedimentation of ferric hydr-oxide. B. H. B.The Basalt of the Stempel, near Marburg. By M. BAUER(Jahrb. f. Min., 1891, ii, Mem. 2:31-271).-This is the concludinginstalment of an elaborate monograph (compare Abstr., 1891, 1440)on the basalt occurring at the hill known as the Stempel, which risesabove the sandstone of the Lahn plateau. This section deals withthe inclusions met with in the rock. These inclusions consist oflimestone, quartz, apatite, nepheline, felspar, amphibolite, titanite,and zircon. 13. H. B