GEOCHEMISTRY.GENERALLY speaking, the period under review has been one ofstleady advance in all the branches indicated in the Report for1930. Perhaps the most important development lies in the increas-ing application of chemical principles t o the description of rocksand mineral deposits. There has been a very substantial outputof physicochemical data for the oxide and other systems, so thatmany problems in igneous petrology, salt deposits, and ores cannow be discussed in ordinary chemical terms. In this way thetheory of chemical reactions in the earth's crust is assuming a moredefinite shape, and steps are being taken to avoid further extensionof the earlier arbitrary descriptive terminology, which has beengenerally regarded as unsatisfactory. Many new minerals havebeen described; but an outstanding feature is the review of theprincipal mineral groups.Pyroxenes (Sundius, Barth), amphi-boles (Winchell), tourmalines (Ward), zeolites (Hey), micas (Jakob),and other important divisions have been critically discussed, withmany additional analyses.In radioactivity, perhaps the most striking development is theconsistent determination of the age of certain minerals, withconsequent dating of the deposits in which they occur. Minera-graphic work includes descriptions of several famous ore-bodies, e.g.,the copper-bearing formation in N. Rhodesia ; the mode of formationof the characteristic structures is being followed up, and the studentnow has the assistance of text-books such as the " Lehrbuch " ofH. Schneiderhohn and the " opaque minerals " bulletin of M.N.Short.Formulation of the silicates continues to be discussed : in manycases new determinations of the unit cell contents have been made,but the interpretation is still troubled by uncertainty as to theextent of " proxy " substitutions : the spinels have been extensivelystudied, with results that fully establish the interchangeability ofcertain atoms. Another important discovery is the existence ofatomic groups, such as 0, in NH,NO,,l that appear to be capableof rotation; here the oxygens, like atoms in solid solution, arenot directly represented by X-ray reflexions.General Geochemistry.Spectroscopic studies have been made of the Katzenbuckelrocks by F. Schroder,la and of tourmaline, diopside, and rocksalt1 J.Arner. Chem. SOC., 1932, 54, 3766.la Jahrb. Min., 1931, [ A ] , 63, 216; A., 5952713 GEOCHEMISTRY .by G. 0. TTild.2 In coloureci minerals thc absorption spectmmchanges with the direction of vibration ; many minerals, especiallythose with uranium h a v ~ been studied by B. Lnnge and W. Eitel,“and by F. Coria.4Several new devices have been proposed for density work.W. Kratschmai has designed a new balance of Westphal type,but giving direct readings for density. A similar instrument byG. Scharffenberg has a circular beam with very widely separatedknife edges. New separating vessels for the centrifuge are givenby W. Kunitz and H. Miiller; S for heavy liquids by S. Klein.9J. L. Rosenholz and D. T. Smith have prepared tables for specificgravity and hardness of minerals.Piperine, n 1.63, is recommendedas a mounting medium by J. H. Martens.llM. M. Stephens l2 finds that some silver minerals may be etchedwith a powerful arc-light. For mineragraphy an important set oftables has been compiled hy M. N. 8hort,lS in n form similar to thewell-known tables for non-opaque minerals by E. 8. Larsen ; colour,hardness, anisotropy and etching properties are listed for the opaqueores, with a section on micro-rcacfions. ilnother importantcontribution is the secoiicl edition (much extended) of the “ Lehrhclider Erzmikrosliopic ” by €1. Sclmeidcrhohn and P. Iimndolir.(Berlin, 1931), supplementecl by ‘ * 1~rzmil;roslio~~ische Bestimnmngs-tafeln ” in a separate volumc.N. Bcreli arid A. Cissarzdiscuss the measurement of reflecting powcr. Microchemicalanalysis, both qualitative and quantitative, is described in Y.Emich’s “ Mikrochemisches Praktikum ” (Munich, 1931). Examplesare given by H. Mueber.16 A. N. Winchell’s ‘“Licro. charactersof . . . artificial minerals ” has been considerably enlarged in asecond edition (New York, 1931). New minerals are listed, withbrief descriptions, by L. 5. Spencer l G n in the .. 12th list of newmineral names ” and numerous physical data have been assembledby the same author.17Centr. Min., 1931, 254, 327, 430; 1932, 18; A., 493.Tsch. min. petr. Mitt., 1931, 41, 435.Ann. SOC. Sci. Bruxelles, 1931, [B], 51, 145; A . , 1931, 1145.Centr. Min., 1932, 221, 348.Ibid., p. 345.Ibid., p. 225. Ibid., p. 90.Ibid., 1931, 244.lo Rensselaar Poly. Inst., Eng. and Sci. Series, No. 34.l1 Amer. Min., 1932, 17, 198.l3 U.S. Geol. Survey, Bull. 825, 1031.l4 2. Krist., 1931, 76, 396; A., 1931, 587.l5 Ibid., 1932, 82, 438.16@ Min. Mag., 1931, 22, 614.l7 “Annual Tables of Constants. . . .” Extracts from vol. 7 (speciall2 lbid., 1931, 16, 532.l6 Centr. Min., 1932, 337.reprint) (Paris)HALLIMOND. 277Much attention is now being given to the distribution of theelements in the earth’s crust. V. M. Goldschmidt l8 and co-workers have produced a series of papers dealing with elementsindividually, such as gallium, boron, scandium, germanium (incoal). Tungsten in Bolivia l9 occurs mainly under lower temperatureconditions than tin-ores.Vanadium has a remarkably wide distri-bution ; it apparently accompanies titanium, and is present insmall amounts in sea-sand and meteorites, in titanomagnetite andin volcanic rocks, as well as in sediments (up to 0.01~o).20 J.Papish and C. B. Stilson21 find that gallium occurs in blendc,galena, etc., but not in some other zinc minerals such as calamine,smithsonite, zincit e.General studies of the distribution of elements have been madeby H. v. Kluber in “Das Vorkommen der chemischen Elementeim Kosmos ” (Leipzig, 1931) for meteorites, planets, and stars.G. Berg’s “Das Vorkommen der chemischen Eleinente auf derErde ” inevitably covers in part the same ground as the series byV. M. Goldschmidt (above). Strontium has a specially interestingdistribution; W.No1122 finds O.lyo (as oxide) in pyroxene andgreater amounts in felspars.Attention has been directed by H. S. Washington23 t o thepossibility that beryllium has been overlooked and included asaluminium, with consequent errors in the comparison of norm andmode for rocks. C. Palache and L. H. Bauer 24 report berylla invesuvianite (9.20%) , cyprine, and barylite, also in milarite.Many contributions have been made to the spinel problem, t owhich reference was made in an earlier report. W. Jander andW. Stamm 25 deduce from conductivity and diffusion measure-ments that some spinels are ionised while others show electronicconductivity. The form y-Al,O, has been studied by I>. S. Belian-kin and N. Dilaktorsky,26 who find that its constants differ fromthose for A1203 dissolved in spinel.T. F. W. Barth and E.Posnjak 27 find further evidence for “ variate atom equipoints ” ;see also F. Machatschki.28 Atom size may be measured by “radius”(W. L. Bragg, V. M. Goldschmidt) or “space-filling ” volumeNudi. Ges. Wiss. Gdttingen, 1931, 165, et ul. ; A., 39, 141, 248, 595, 926.F . Ahlfbld, Chem. Erde, 1933, 7, 121 ; A., 596.2o K. Jost, ibid., p . 177.21 Arner. Min., 1930, 15, 821; A., 1931, S17.22 Naturwiss., 1931, 19, 773; -4., 1931, 1391.23 Amer. Min., 1931, 16, 37.25 2. anorg. Chem., 1931,199, 165; A., 1931, 999.26 Centr. Min., 1932, 229.2 7 J . Wash. Acad. Sci., 1931, 21, 255; A . , 830.28 2. Krist., 1932, 82, 348.24 Ibid., p. 469; A., 1107278 GEOCHEMISTRY.(T.W. Richards, J. J. Thomson z9) ; W. Biltz 30 and others havecarried out an extensive study of molecular and atomic volumes,mainly on an additive basis. G. Natta31 has examined hydrogenchloride, bromide, etc., and finds relatively large atomic sizes forthe halogens. It is interesting to recall that the original halogenvolumes given by Wasastjerna depended on the experimental sideon a small size assigned to hydrogen in the dissolved halide.Oxide Xystems.G. W. Morey 32 has given a valuable discussion of silicate chemistrywith many references to earlier literature on synthesis, particularlyby the Geophysical Laboratory. Cr,O, and A1,0, form a continuousseries of mix-crystals ; and Si02-Zn0-A1203 (E. N. Bunting) yieldsZn,SiO,,ZnAl,O, and mullite, with bearing on the making of zinc-retorts.33 Solutions of sodium chloride under pressure have beenstudied by L. H.Adams and R. E. Hall.3* In Mg0-MgC12-Hz0,35brucite yields, with MgCl2,6H,O and solution, a magnesiancement. Many compounds in Ca0-Si02-A1203-H,0 have beendescribed in an extensive series of papers by S. Nagai,36 both a tatmospheric pressure and with high pressure and moderate temper-ature; sodium carbonate solution is used to separate the products.The same author, also W. Masgill, G. M. Whiting, and W. E. S .Turner,37 have studied the silicates formed by heating chalk andsilica. CaO-Na,0-,41203 38 yields two ternary compounds.The volatility of silica in steam is discussed by G. W. Morey.39C. J. van Nieuwenburg and H.B. Blumenda14* have volatilisedsilica in supercritical steam : kaliophilite is altered to leucite andorthoclase, while nephelite yields analcite and albite ; carbondioxide inhibits these reactions. Titanium and stannic oxides arenot volatile under these conditions, but molybdenum and tungstenThe sizes given by the c c radius”method are often quite at variance with the c c additive ” volumes ; cf. A. F.Hallimond, Min. Mag., 1927,21, 277; 1928, 21,480; 1929, 22, 70.29 Phil. Mag., 1922, 44, 657; 43, 721.30 2. anorg. Chem., 1932, 203, 277, etc.31 Mem. R. Accad. d’Italia, 1931, 2, 1.32 Annual Survey of Amer. Chern., 1930, 5, 457.33 E. N. Bunting, Bur. Stand. J . Res., 1931, 6, 946; 1932, 8, 279; A., 1931,34 J . Wash. Acad.Sci., 1931, 21, 183; A., 1931, 793.35 C. R. Bury and E. R. H. Davies, J., 1932, 2008.3ti 2. anorg. Chem., 1932, 206, 177, etc.J . SOC. Glass Tech., 1932,l6, 94.36 L. T. Brownmiller and R. H. Bogue, Bur. Stand. J . Res., 1932, 8, 289 ;39 G‘eophys. Lab. Paper, No. 786.40 Rec. trav. chim., 1931, 50, 989; A., 1931, 1381.1010 ; 1932, 547.A . , 574HALLIMOND. 279trioxides will react with lime to form CaMoO,, etc. ; copper is alsovolatile. Carbon dioxide under high pressure attacks the silicatesre~ersibly.~l K. Bito, K. Aoyama, and M. Matsui4, find thatcalcium carbonate dissociates a t about 915" under one atm. ofcarbon dioxide ; fresh crystals require a slightly higher temperature.The system K,O-CaO-SiO,, important for glass-making, has beendetermined by G.W. Morey, F. C. Kracek, and N. L. B~wen,*~and the behaviour of K,Si40, under pressure has been investigatedby R. W. Goranson and F. K r a ~ e k . ~ ~Systems containing iron react with platinum vessels ; in additionthe two iron oxides react with the furnace gas. Complete successin these experiments has not yet been obtained, but a number ofsystems have been investigated over a considerable range of con-ditions. By using electrolytic iron crucibles in nitrogen, N. L.Bowen and J. F. Schairer 45 have explored the system ferrous oxide-silica. Ferric oxide appears, up to 11%, which diminishes sharplyon addition of silica; all attempts t o produce FeSiO, failed(although iron-rhodonite is common in slags), MgO-FeO-Fe,O,in air a t one atm.has been investigated by H. S. Roberts and H. E.Merwin ;46 equilibrium is attained slowly, and the alundum crucibleswere protected by an adherent layer of the mixture; when homo-geneous, the preparation was treated by the usual quenchingmethod; one interesting feature is the formation of solid solutionsnot only between MgO,Fe,O, and iron oxide but between thatcompound and magnesium oxide, a further contribution to thecomplex problem of the spinels. J. H. Andrew and W. R.Maddocks 47 describe solid solutions of FeS in Fe,SiO,.The system potassium sulphate-water under pressure has beeninvestigated by L. H. Adam~.~8 G. Tunell and E. Posnjak49 havecompared the natural oxidation of sulphide ore-bodies with thehehaviour of the system Fe,O,-CuO-SO,-H,O (part) ; goethite,tenorite, brochantite, antlerite, and 3Fe,03,4S03,9H,0 were obtained.S. G.Lasky 49a discusses the application of the phase rule to iron oresin limestone.Several ternary compounds in Na,O-B20,-H,O have been pre-I1 W. Weyl, Glastech. Ber., 1931, 9, 641.42 J . SOC. Chem. Ind. Japan, 1932, 35, 191.43 J . SOC. Glass Tech., 1930, 14, 149; 1931, 15, 57; A., 1931, 1011.44 J . Physical Chem., 1932,36, 913.45 Amer. J . Sci., 1932, [v], 24, 177; A . , 997.46 Ibid., 1931, 21, 145; A., 1931, 310.47 J . Iron and Steel Inst.. 1932 [adv. copy] ; A., 997.4s J . Amer. Chern. Soc., 1932, 54, 2229 ; A., 810.49 J . Physical Chem., 1931, 35, 929; A., 1931, 800.49a Econ. Beol., 1931, 26, 486280 GEOCHEMISTRY.pared by U.Sborgi; 50 CaO-Ye0 has also been studied by J. Kon-arzewski 51 with reference to Portland cement. Thermal data forsilicates of Ca, Fe, Mg are given by W. A. Roth and H. T r o i t ~ s c h , ~ ~also by H. Wagner.53 V. A. Vigfusson 54 has prepared hydratedcalcium silicates. Further data for gypsum-anhydrite atre givenby R. Nacken and K. Fill,55 and also by L. Cha~sevent.~~ Lithi-ophilite (LiMnPO,) has been prepared by F. Zambonini and L.Malossi 57 in phosphoryl chloride vapour. Phosphates related tothe apatite group have been prepared by precipitation, as well asby heating a t 1100", by G. Trome1.58 A. Sanfourche arid J. Henry 59note a false equilibrium in the action of water on CaHPO,. Musco-vite 60 has been prepared hydrothermally by heating the colloidmixture in a pressure bomb for 5 days a t 300".Petrology.Rock analyses are very widely scattered in the literature, arid itis impossiblc to deal with them adequately in the present Report.They are mainly intended for descriptive purposes, though a certainproportion of papers on the igneous rocks are accompanied bytheoretical discussions on the mode of formation.A valuabletext-book on petrology has been prepared by F. F. Grout : " Petro-graphy and Petrology" (New York, 1932). The latter term isdefined to include the discussion of theory, and the book will givethe student a very clear account of the present state of speculationin this subject. Development has been hindered by a terminologywhich has not yet been successfully revised.Actually the totalnumber of petrological terms to-day is about 1300,60u including notonly all the rock names but the descriptive terms ; with the progres-sive abandonment of a substantial proportion of the names, thelist should reach manageable proportions. Throughout the workthe student is assumed to have a fully competent knowledge ofchemistry, physics, and mineralogy : there is a brief account ofpetrographical methods in the form of a series of problems, but thedegree of condensation in this part of the book may be gatheredGaxzetta, 1932, 62, 3 ; A., 341.6 1 Rocz. Chem., 1931, 11, 516, 607; A . , 1931, 1010, 1373.5 2 Arch. Eisenhuttenw., 1932-1933, 6, 79.5 3 2. anorg. Chem., 1932, 208, 1.54 Amer. J. Sci., 1931. [v], 21, 67; A., 1931, 310.5 5 Tonind.-Zfy., 1931, 55, 1194.5 6 Cowpt. r e d . , 1932, 194, 786.5 7 2. Krist., 1931, 80, 442; A . , 38.5 8 2. physikal. Ohem., 1932, 158, 422; 2. anorg. Chenz., 1932, 206, 227.5B Compt. rend., 1932, 194, 1940.6o ITT. Noll, Naturwiss., 1932, 20, 283.60a A. Hokes, " The Nomenclaturo of Petrology," 2nd Ed. (London, 1928)HALLIMOND. 281from the paragraph dealing with rock-analysis : ‘‘ Problem &Tomake a chemical analysis of a rock. Method--Refer to H. S.Washington. . . . ” It may be some time before the painstakingstudent is free to attack Problem 7 ! The descriptions are mainlybased on examples chosen from North American occurrences ;evidence for the operation of the principal rock-forming processeshas been clearly set out and the difficulties are not evaded.Butagain it must be emphasised that these chapters assume previoustraining, indeed there is some risk that so lucid a text-book mayencourage a superficial acquaintance with “ petrology ” in studentswho lack the necessary groundwork of the older sciences.“ Metamorphism ” by A. Harker (London, 1932) will be an essen-tial text-book for the more advanced student. Mineralogicalchanges produced by heating, chemical alteration, and pressureare systematically described, with many illustrative examplestaken mainly from British occurrences. The development of por-phyroblastic structures is traced with reference to the “ crystal-lising power ” of the mineral, which determines microstructures ofa type quite distinct from those due to the crystallisation-sequencein igneous rocks.More than 200 drawings are very effectivelyused in place of photomicrographs.Among numerous descriptions, mention may be made of papersby Romer,61 who describes the gas, incrustations, and dacitoidlavas of Mt. Pelke. Liparite from the Crimea,62 containing Fe 0.44,alk. 8.75%, might be used for glass manufacture. A. Holmes andH. F. Harwood 63 have given an extensive description of volcanicrocks from Uganda. Much discussion has recently centred uponthe question how far an igneous intrusion can assimilate the wall-rocks : s. R. Nockolds 64 describes the process in a granite-green-stone contact from the Isle of Man; other instances are given byH. H. Thomas and W. Campbell Smith,G5 basic xenoliths in aBrittany granite ; by H.C. Horwood,66 granite-gneiss and granite-limestone contacts in Ontario; by L. A. N. Iyer 67 for granites inIndia; also a detailed study of granite slate contacts in Cornwall,by A. Brammall and H. F. H a r w o ~ d . ~ ~ ~ Differentiation withoutcontamination has been studied by F. F. Osborne and E. J.61 Compt. rend., 1932, 195, 393; A., 1015.62 Trans. State Ins?. Test. Building Mat., 1930, 34, 33.63 Quart. J. Geol. SOL, 1932, 88, 370; A., 1015.64 Min. Mag., 1931, 22, 494; A., 1931, 1029.135 Quart. J. Geol. SOC., 1932, 88, 274.66 Trans. Roy. Soc. Canada, 1931, [iii], 25, IVY 227 ; A., 359.67 Rec. Geol. Surv. India, 1932, 65, 445; A., 1107.67a Quart. J . CTeol. Soc., 1932, 88, 171; A., 715282 GEOCHEMISTRY.Roberts,68 who redescribe theShonkinSaglaccolith ; by L. Jugovics,60for dacites in Bohemia ; and by A.Vendl,70 for Hungarian andesites.E. Lehmann 71 derives basanite, trachyte, etc., in Nyassaland froma basaltic magma, and a similar explanation is given for basicflows in West Greenland. 72General theory includes a discussion of the earth's interior byA. A. Bless,73 who estimates the temperature as lo5 degrees, androck-classifications by A. Johannsen 74 and E. TrOger.'5 A revisionof the minerals postulated in calculating the " norm " of a rockhas been proposed by T. F. W. Barth 75a and criticised by C. E.Tilley.76 P. Eslrola 77 objects that the idea of a lighter sial layeris not supported by the frequent occurrence of granites in thepre-Cambrian, which rather indicates crystallisation-differentiation.Much attention has been given to the composition of the residualliquids formed during the crystallisation of a granite : C.N. Fenner 78has pointed out that in some cases an increase in iron/magnesiaratio should occur, a fact which has not always been taken intoaccount; H. A. Powers 79 finds that in lavas from California theresidual liquid was enriched in iron. A general theoretical dis-cussion of this problem has been given by P. Niggli.80 Experimentsby R. W. Goranson 81 show that water, which becomes concentratedin the residue, has an important influence on the crystallisation ofgranite. Under 10 km. cover, a granite with 1% H,O would beginto crystallise a t 1025"; at 700" the residual would contain 6.5% ofwater, and would continue to crystallise till below 500", the resultbeing 85% granite, 10% aplite, 5% quartz veins. Under only4 km., the pressure will equal the hydrostatic head when the temper-ature falls to 950", so that liquid can then be expelled from thereservoir ; this, the author considers, might result in the formationof two fluid phases.O S Amey.J. Sci., 1931, [v], 22, 331; A , , 1931, 1265.G@ Tsch. min. petr. Mitt., 1932, 43, 156 : A., 1107.7O Ibid., 1932, 42, 491.Ibid., 1931, 41, 8.72 H. Nieland, Chem. Ede, 1931, 6, 501.7 3 Proc. Nut. Acad. Sci., 1931, 17, 225; A . , 1931, 81G.7 " A Descriptive Petrography of the Igneous Rocks " (Chicago, 193 1 ).i 5 Jahrb. Min., 1931, [ A ] , 62, 249; A., 1931, 1391.i 5 a Tsch.min. petr. Mitt., 1931, 42, 1 ; A., 1931, 1391.i 6 Ibid., 1931, 42, 1 ; 1932, 43, 68; A., 926.i7 Ibid., 1932, 42, 455; A., 715.7 8 Min. Mag., 1931, 22, 539; A., 1931, 1390.7 9 Amer. Min., 1932, 17, 253.Rec. trav. chirn., 1932, 51, 633; A . , 829.81 Amer. J . Sci., 1932, [v], 23, 227; 1931, 22, 483; A., 492HALLIMOND . 283RadioactivityRegular use is now being made of the P b : U and other ratios forcomputing the age of rocks and minerals. C, N. Fenner 82 obtains2779 x lo5 years for the age of a monazite crystal, agreeing wellwith the value for uraninite from the same quarry. Thucholitegives 250 x lo6 while 0. B. Muench finds 373 X lo6years for cyrtolite from Bedford, N.Y., and 571 x lo6 for that fromOntario.On the other hand, (Mlle.) E. Gleditsch and B. Qviller 85report unduly low values for uranothorites. Kolm, the Swedishuranium-bearing shale, is proved by R. C. Wells and R. E. Stevens 86to have an age of 458 x 106 years. G. Elsens7 and (Mlle.) E.Gleditsch and S. Klemetsen 88 contribute to the investigation ofactinium content. Lead in rocks is for the greater part not ofradioactive origin.89 A. Holmes 90 remarks that the total lead isfrom 4-50 times the generated lead ; lead ores can have been derivedfrom granitic magmas provided that the age of the earth is notmore than 16 x 108 years. C. S. Piggot 91 gives data for the radiumcontent of granites and of Hawaiian lavas. In granite the element isapparently chiefly associated with the Portuguese graniteshave yielded high radium values, and schists the lowest.93 Leadmay be included in crystals of sodium and potassium chloride;possibly it may occur in marine salts.94 Natural waters some-times contain radium,94* but it is largely eliminated by the presenceof sulphate ; water from petroleum wells, free from sulphate, had ahigher radioa~tivity.~~Minerals.Elements.-Few, if any, of the reported syntheses of diamondhave survived further tests ; M.K. Hoffmann 96 has repeated, with82 Amer. J . Sci., 1932, [v], 28, 327; A., 595.83 A. Faessler, Centr. Min., 1931, [ A ] , 10; A., 1931, 930.84 Amer. J . Sci., 1931, [v], 21, 350; A., 1931, 594.Phil. Mag., 1932, [vii], 14, 233; A., 1015.8 6 J . Wash. Acad. SC~., 1931, 21, 409; A., 1931, 1391.8 7 Chem.Weekblad, 1931, 28, 714; A., 139.89 G. von Hevesy and R. Hobbie, Nature, 1931,128, 1038; A., 139.91 Amer. J . Sci., 1931, [v], 21, 28; 22, 1 ; A., 1931, 332, 930.93 G. Costanzo, Rev. Ch;m. pura appl., 1931, [iii], 6, 17; A., 494,94 Xaturw+s., 1932, 20, 86.94a E.g., J. L. Bohn, J . Franklin Inst., 1930,210,461 ; P. Forjaz, Rev. Chim.pura app?., 1931, [iii], 6 , 1 5 ; J. A. Hootman, Amer. J. Sci., 1931, [v], 22, 453.95 W. Salomon-Calvi, Petroleurn, 1931, 27, 652; A . , 1931: 1145.g 6 Centr. Min., 1931, 214.Compt. rend., 1932, 194, 1731; A., 715.Ibid., p. 1039; A., 139.C. S. Piggot and H. E. Merwin, ibid., 1932, [v], 23, 49; A ., 139284 GEOCHEMISTRY.negative results, Hoff’s synthesis by means of the carbon arc inliquid air E.Reuniiig ‘37 discusses the origin of the rich diamonddeposits of S. W. Africa. Graphite is the subject of a monograph,“ Der Graphit” by 0. Kausch (Halle, 1931). Volcanic sulphurhas been analysed by W. Geilmann and W. Biltz;98 native sulphuroccurs (inside oxidised pyrite concretions) in nacrous scales of theform S 111, for which the name rosickyite is proposed by J. Sekanimx9gGold in the spatliic veins of Siegerland occurs in pyrite as well as inbismuth minerals, representing two stages of the hydrothermaldeposition.1 Gold in jacutinga, according to E. de Oliveira,2 is a,secondary deposit from acid chlorine-bearing solutions due to oxitl-ation of pyrite. Tn gravels gold has been reputed to “ grow again ”and P. W. Freise3 shows that small amounts of humic acid inground water will slowly dissolve gold in the absence of oxygen.Platinum in the famous “ Merensky horizon ” is shown spectro-graphically to occur in the sulphides in solid solution; in dunite,where sulphides are deficient, the platinum is in the metallic form,associated with chromite; only the sulphide ores give rise tosecondary platinum minerals on weat hering.Several primaryplatinum ores are analysed by A. G. Betechtin; Fe = 10-150/,,also Cu, Ir, Ni. Osmiridium is shown by 0. E. Zvjagintsev andB. K. Brunovski to contain substantial amounts of ruthenium,rhodium, etc., all in solid solution. Native silver has been shown by(Sir) H. C. H. Carpenter and M. S. Fisher to have a grain structuredepending on the temperature of deposition or subsequent heating.At Konigsberg silver occurs largely in secondary forms ; mercury,antimony, and nickel are present in some veins, which R.Stmenregards as of Temiskaming type. L. Tronstad9 concludes thittsilver may be deposited a t other points as well as the intersection oflodes with fahlbands. The genesis of the L. Superior copper-silverdeposits is discussed by K. Nishio,1° and by T. M. 13roderick.10a 11:. 13.Yapenfus l o b has described the “ bedded” copper ores of Nova Scotia.s7 Jahrb. Min., Beil.-Ud., 1931, [-4], 64, 775; A., 492.98 Z. anorg. Chem., 1931, 197, 422; A., 1931, 816.g9 2. Krist., 1931, 80, 174; A., 1931, 1390.* J. M. Huttenhain, Tsch. min. pstr. Mitt., 1932, 42, 355; A., 490.Ann. Acad. Brasil.Sci., 1931, 3, 151; A., 829.Metall u. Em, 1930, 27, 442; Econ. Geol., 1931, 26, 421; A., 1931, 1390.* Siebert Festschr., 1931, 257.5 Gorni Zhur., 1930,108, No. 1, 152; A., 140.Z. Krist., 1932, 83, 172; A., 1107.7 Bull. Inst. Min. Met., 1932, No. 330; A., 595.Tidsskr. Kjerni Berg., 1931, 11, 16; A., 1031, 331.Ibid., 1932, 12, 15, 28; A., 494.lo Proc. World Eng. Congr., Tokyo, 1931, 37, 499; A., 596.loa Econ. Geot., 1931, 26, 841, lob Ibid., p. 314HALLIMOND. 285Halides.-Salt domes are usually regarded as the result of theplastic flow of bedded salt deposits. In detail, however, they giverise to many difficult problems, such as the explanation of theirassociation with petroleum, and the origin of the associated calciumsulphate and sulphur; these points are discussed by M.Stuart,llL. Owen,l2 and E. de G01yer.l~ Salt pans in Brazil form on thePermian outcrops and are of three types, containing nitrates,carbonates, and ~u1phates.l~ F. Heidorn l5 records magnesiumfluoride with bitumen from the Zechstein. Radium fluoride isapparently present in isomorphous mixture in a radioactive fluoritedescribed by F. L. Hess.16 M. Kahanowicz l7 finds that bluefluorescence in sodium chloride is identical with that for metallicsodium, which has been suggested as the colouring matter. Halidephase-rule systems include that for (K, Na)Cl-H,O, by E. Cornecand H. Krombach,17 and the carnallite system by N. S. Kurnakow,D. P. Manoev, and N. A. Osokoreva.ls G. Silberstein l9 describes" pipes '' in limestolit.a t Hopunvaara, with magnetite and fluoritein alternate layers.XuZphides.-Staiinite has been recorded from TasmaniaYBo Spain,21and from British Columbia; 22 these are of interest in connexionwith the problem of cassiterite formation, and descriptions of Boliviantin veins have been given by G. W. Lindgren and A. C. Abbott 23(Oruro), F. Ahlfeld 24 (Uncia Llallagua), localities where the veinsare related to dacitic intrusive rocks. R. Herzenberg25 has de-scribed a new mineral lcoEbeckin (Sn2S,), cementing cassiterite(not confirmed by Ramdohr).The veins and telluride minerals of Kalgoorlie are describedin detail by F. L. Stilwell; 26 H. Borchert 27 gives etching lists fortellurides ; L. Toliody 28 has analysed hessite ; G. Vavrinecz 29describes antimony-rich enargite, from Hungary.X-Ray methodsl 1 J . Inst. Petrol. Tech., 1931, 17, 338; A., 1931, 931.l 2 Ibid., p. 334; A., 1931, 931.l4 F. W. Freise, Chem. Erde, 1932, '7, 24; A., 596.l5 Centr. Min., 1932, 356.l C Amer. J. Sci., 1931, [v], 22, 215; A., 1931, 1146.l7 Ann. Chim., 1932, [XI, 18, 5. l 8 Kali, Russia, 1932, No. 2, 25.Z o F. L. Stilwell, Proc. Austral. Inst. Min. Met., 1931, 1 ; A., 1931, 1029.21 S. Piiia de Rubies, Anal. Pis. Quim., 1931, 29, 699; A., 248.22 H. C. Gunning, Econ. Geol., 1931, 28, 215.23 Ibid., p. 453.2s Centr. Min., 1932, 354.26 W . Austral. Geol. Surv. Bull. 94, 1929; A., 495.27 Jahrb. Min., 1930, [ A ] , 61, 101.28 2. Krist., 1932, 82, 154; A., 595.29 B&n. KohBs. Lapok, 1931,64, 438; Chem. Zentr., 1936, i, 931.l3 Ibid., p.331.TSCJL. min. petr. Mitt., 1931, 41, 197.24 Ibid., p. 241286 GEOCHEMISTRY.have been used by F. A. Bannister and M. H. Hey 30 to determinethe minerals of S. African platinum concentrates, and for thedistinction of pyrite from m a r ~ a s i t e , ~ ~ the latter result confirmingthe earlier work of Allen and others. Bushveld nickel veins arediscussed by R. D. Hoffman.32" Unmixing " has been studied for covellite-chalcocite byA. M. Bateman and S. G. Lasky; 33 for chalcopyrite-blende andcubanite by E. Clar ; 34 and for chalcopyrite-cubanite-pyrrhotiteby WT. H. Newhouse.35 General descriptions of the correspondingmicrostructures have been given, especially by G. M. S ~ h w a r t z . ~ ~Several detailed accounts have been given of N.Rhodesian copperdeposits,37 which are usually regarded as impregnations from theneighbouring granite.Sulvanite, CU,VS,,~~ has been found in Utah. L. W. Staplesand C. W. Cook39 describe the molybdenite veins of Climax, Col.Oxides.-0. Miigge 40 describes a method for determining thetemperature of formation of quartz by heating a t 600". Amethystmines in Brazil are described by R. Brauns;41 according toJ. H ~ f f m a n n , ~ ~ amethyst colours can be imitated by exposingsilicate glasses to radium rays. Colour in spinel is shown byK. Schlossmacher 43 to be due to 1-4% of Fe (Coy Mn, Cr absent) ;intermediate colours are due to reduction.Galaxite, a new spinel, MnO,Al,O,, is described by C. S. Rossand P.F. Kerr44 with alleghanyite (5Mn0,2Si02). M. Donath45finds 2.42% ZnO in chromite from Ramberget; chromite fromTogoland has been analysed by N. IC~uriatchy.~~ H. H. Read47has described the formation of corundum-spinel xenoliths fromAberdeenshire.Water-soluble humus plays a great part in the formation of lakeiron ores ; 0. Aschan 48 has analysed the organic matter in Finnishlake waters. S. Goldsztaub 49 describes the formation of parallelgrowths of haematite on dehydrating natural ferric hydroxides ;30 Min. Mag., 1932, 23, 188; A., 1014.32 Econ. Geol., 1931, 26, 202.34 Centr. Min., 1931, 147.36 Econ. Geol., 1931, 26, 739.38 Arner. Min., 1931, 16, 667.42 2. anorg. Chem., 1931,196, 225; A., 1931, 579.4J 2. Krkt., 1931,76, 370, 377; A., 1931, 459, 545.44 rimer.Min., 1932, 17, 1 ; A., 1228.$ 5 lbid., 1931, 16, 484; A., 1107.4 6 Compt. rend., 1931, 192, 1669; A., 1931, 1029.4 7 Geol. Mag., 1931, 68, 446.48 Rrkiv Kenzi, Min. Geol., 1935, 10, No. 14, I ; d., 716.49 Comnpt. rmd., 1931, 193, 533; A . , 1931, 1390.31 Ibid,, p. 179.33 Ibid., 1932, 27, 5 2 .35 Amer. Min., 1931, 16, 334.37 See Econ. Geol., 1931-1932.39 Ibid., p. 1.41 Centr. Min., 1932, 97. 2. Krist., 1932, 82, 451; A , , 889KALLIMOND . 287the stability relations of these minerals have been discussed byG. Tunell and E. Posnjak 50 with reference to the theoretical con-clusions of J. W. Gruner. Further descriptions of the importantWabana iron ore have been given by A. 0. Hayes.51 Perhaps thegreatest iron ore masses in the world are the Brazilian itabirites,which occur as stratified pure red hzmatite and as micaceousschist.Z2 The peculiar banding of the L.Superior iron formationis attributed by R. J. Hartman and R. M. Dickey 53 to Liesegangeffects ; secondary ores are described by C. K. Leith.53aW. J. O'Leary and J. Papish 54 find up to 0.25% Cr in ruby.A. Achenbach 55 finds that artificial gibbsite passes into boehmiteabout 200" and dehydrates further at 350". W. Bussem andF. Koberich 56 describe the dehydration of brucite to periclase inparallel orientation. Analyses are given for pyroaurite 57 andhydromagnesite. 58 Microscopical studies of the manganese oxideshave been made by S. R. B. Cooke, W. Howes, and A. Emery,59also by J.Orcel and S. Pavlovitch.6O G. Natta and M. Baccaredda61find both Sb204 and Sb,O,, with calcium, in various antimonyochres. C. Zapffe has studied deposition of manganese fromwater supplies, sometimes by bacteria.61aCarbonates.-Bacterial precipitation of lime is described byH. Fischer, W. Bavendamm, P. Kalantarian and A. Petrossian,6zwho find a new bacterium, B. Xewanense. X-Ray investigationsby F. K. Mayer 63 show the presence of vaterite, changing to aragon-ite and calcite, in the shells of fresh-water snails. H. Wattenberg 64has suggested that liquid carbon dioxide could be formed under thepressures that obt'ain in ocean depths. Conditions for the pre-cipitation of dolomite have been discussed by 0. Biir 65 and H.Econ. Geol., 1931, 28, 337, 442, 783, 894; 27, 189; A., 1931, 800.51 Ibid., 1931, 26, 1.53 E.A. Scheibe, Arch. Eisenhiittenw., 1931-1932, 5, 391 ; A., 492.j3 J . Physical Chem., 1932, 36, 1129; A . , 492.j30 Econ. Geol., 1931, 26, 274.64 Anher. Min., 1931, 16, 3 4 ; A., 1931, 455.5 5 Chern. Erde, 1931, 6, 307; A., 1931, 1029.5 6 2. physikal. Chem., 1932, [B], 17, 310.57 E. Aminoff and R. Broom6, K . Svenska Vetenelcaps Akad. Handl., 1931,58 G. R. Levi and D. Ghiron, Gazxetta, 1932, 62, 218; A , , 696.5n Amer. Min., 1931, 16, 209.Go Bull. Soc. franp. Min., 1931, 54, 108; A., 1106.Atti R. A d . Lincei, 1932, [vi], 15, 389; A., 829.61a &on. Geol., 1931, 26, 799.G3 Chern. Erde, 1931, 6, 239; A., 1931, 596.64 Nature, 1933, 130, 26; A , , 539.66 Centr. Min., 1932, [A], 46; A., 1106.[iii], 9, No.5, 4 ; A., 1931, 1029.63 Zentr. Bakt. Par., 1932, 85, 431288 GEOCHEMISTRY.Udluft.66 E. Kohler 67 finds that schaumspat is a pseudomorphof dolomite after gypsum. J. Klarding has studied the roastingof ferrous carbonate, with formation of Fe,O,. Rocks consistingof dolomite, with zones of transition to magnesite and to siderite,occur in the S. U r a l ~ . ~ ~ Hydraked cupric carbonates, with malachite,have been prepared by V. Auger and Mme. P~ulenc-Ferrand.~~A curious observation has been made by F. Stober,71 who finds thaton imitating the formation of Fontainebleau calcites by growingsodium nitrate in sand, the rate of growth is very greatly increasedin the presence of the sand. Ik'. Taboury 72 has found efflorescenceof calcium acetate upon calcite specimens that had been stored inoak cases, due to acid from the wood.Silicates.-G.W. Ward 73 has carried out a very thoroughinvestigation of the black tourmalines ; optical properties aregiven, with several new analyses. While accepting the ordinarychemical replacements, he concludes that it would be futile topropose new molecules; a simple formula cannot be found.F. Machatschki 74 proposes for tourmaline the (physical) formulaXYSB,SiGH,03 where X = (Cu, Na), Y = (Li, Mg, &In, Fe, h l ) ;NaSi is replaceable by CaAl, and SiMg by AlAl.'' Green-earth " in the Tyrol occurs between volcanic rocks andlimestone ; it is compared by K. Hummel 75 with glauconite, and itsformation is attributed to halmyrolysis, i.e., submarine alteration,of igneous rock.Parase-piolitc has been found by H. Meixner 76in the Styrian magnesite deposits. Ashtonite 77 and cbinoptilolite 78are new aluminosilicates related to ptilolite. Zunyite fromGuatemala has been analysed by C. P a l a ~ h e . ~ ~ G. Liberi *O deducesthe formula 4Be0,Al,03,7Si0, for beryl from Erythrzea : danburitehas been described by Z. Harads.slE. S. Larsen and W. T. Schaller 82 describe serendibite from aG t iti76 8ti9i oi l727 3747 57 6" - , I7 88 08182Z. deut. geol. Ces., 1931, 83, 1 ; A., 1931, 1391.Chem. Erde, 1931, 6, 257 ;2. anorg. Chern., 1932, 207, 246.L. M. Miropolski, Bull. Acad. Sci. U.IE.iS.S., 1935, 820; rl., 1015.Compt. rend., 1932, 194, 78s ; A., 481.Chem.Erde, 1931, 6, 357; A., 1931, 1030.BUZZ. SOC. chirn., 1931, [iv], 49, 1289; ' I . , 3!J.Arney. Min., 1931, 16, 146; A . , 38.2. Krist., 1929, 70, 211; 71, 45; A., 1931, 595.Chern. Erde, 1931, 6, 468; A., 140.Tsch. min.petr. Mitt., 1932, 43, 182; A., 1107.E. Poitevin, Amer. Min., 1932, 17, 106.W. T. Schaller, ibid., p. 128; A., 1228.Ann. Chim. Appl., 1932, 22, 544; A., 1106.Z . Krist., 1931, 79, 349; A., 1931, 1266.Amer. Min., 1932,17, 457; A., 1228.., 1931, 596.i s Ibicl., p. 304HALLIMOND. 289limestone-granite contact. Dumortierite from India has beenaiialysed by S. K. Chatterjee.8,The hauyne group is particularly complex: T. F. W. Barth 84suggests physical formulz, and L. H. Borgstrom 85 proposes thesubstitution Ca,Na.D. S. Beliankin renames a sulphate-cancrinitewischnewite.86 Helvite has been analysed by H. B~wley.~'Sodalites have been aiialysed by K. Haraguchi 88 and by W.Brendler. 89 It is sometimes difficult to distinguish nepheline fromsodalite ; a method with X-rays, applicable to thin sections, has beendeveloped by F. A. Bannister,9o with several analyses by M. H. Hey ;similar methods are given for analcime and l e u ~ i t e . ~ ~ The scapol-ite group has been reviewed by L. H. Borg~trorn,~~ who regards themas isomorphous mixtures of type (NaAlSi,O,),, in which albitemay be replaced by anorthite, and NaCl by CaCO,, CaS04, &Na,CO,,&Na,SO,, Ca atoms replacing Na. F. Zambonini and V. Caglioti 93discuss new analyses of sarcolite.Among the hydrated silicates, H.Hueber and W. Frehg4 findthat " kupferpecherz " is a limonitic chrysocolla, isotropic. A.Schoep 95 concludes that plancheite from Katanga is variableand in part identical with shattuckite, in part with bisbeeite fromArizona ; katangite is chrysocolla. Willemite prepared by A. Karl 96 isfluorescent like the natural mineral. Bultfonteinite, 2Ca( OH,F),,SiO,,a new mineral from Kimberley diamond mines, is describedby J. Parry, A. F. Williams, and F. E. 'M7right.g7 S. Iimori,T. Yoshimura, and S. Hata 98 describe nagatelite, a new pegmatitemineral resembling allanite. Xanbornite 99 has the compositionBaSi205. Analyses have been made of lessingite, serandite,spadaite,, joaquinite, gadolinite, pumpellyite, bavenite., G.W.Bain has discussed the formation of chrysotile83 Rec. Geol. Surv. India, 1931, $5, 285; A., 247.84 Amer. Min., 1932, 17, 466.8 6 Centr. Min., 1931, 190; A., 249.87 J . Roy. Soc. W. Australia, 1932, 18, 83.8a Chikyu, 1928, 10, 262. 89 Centr. Min., 1932, [A], 42; A., 1106.Min. Mag., 1931, 22, 569; A., 1931, 1390.91 Ibid., p. 469; A., 1931, 595. O3 2. KriSt., 1931, '76, 481.O3 Compt. rend., 1931, 192, 967; A., 1931, 706.94 Centr. Min., 1931, 296. 95 Bull. SOC. franp. Min., 1930, 53, 375.O 6 Compt. rend., 1932, 194, 1743; A., 715.97 Min. Mag., 1932, 23, 145; A., 1015.98 Sci. Papers Inst. Phys. Chem. Res. Tokyo, 1930, 15, 83; A., 1931, 459.g9 A. F. Rogers, Amer. Min., 1932,17, 161; A., 1228.1 Trans. Inst. Econ. Min. Met., MOSCOW, 1930, Nos.44, 46.a Amer. Min., 1931, 16, pp. 344 and 231 resp.85 2. Krist., 1931, 76, 481; A., 140.Ibid., 1932, 17, pp, 308, 97, 338, 409 resp. ; A., 1228.Econ. Geol., 1932, 27, 39.REP.-VOL. XXIX. 290 GEOCHEMISTRY.Pyroxemx-N. Sundius4 has given a very full account of thetriclinic (Fey Mn, Ca) pyroxenes. Like the carbonates, they form aseries of incompletely miscible crystals, the intermediate membersbeing sobralite (Fe, Mn), bustamite (Mn, Ca), and hedenbergitc(Fe,Ca)SiO,. Bustamite does not form a complete series ofsolutions with rhodonite, and the optical properties are not continu-ous : it is suggested that bustamite is a ferriferous wollastonite;a wide gap between bustamite and wollastonite is attributed to theformation of pseudo-wollastonite a t higher temperatures. X-Raydata for enstatite are given by B.Gossner and F. Mussgnug;F. Rodolico gives analyses of diopside and tremolite from Italy.A pyroxene from S. Africa 7 contains 1.96% Cr,O,. T. F. W. Barth *records a titaniferous augite (TiO,, 3-75%), and has discussed theoccurrence of pyroxenes in basalt; this subject has been furtherexamined by S. T~uboi.~*Amphiboles.-Since the general acceptance of amphibole formulaewith (F, OH) as an essential constituent, the whole question of thestability relations of these minerals has come under review. Theformulation is further discussed by W. Kunitz lo and by E. Posnjakand N. L. Bowen,lOa who agree with the tremolite formula ofSchaller and Warren; the water is lost a t about goo”, when thecrystal changes to pyroxene and cristobalite ; a mineral obtainedfrom the dry melt proves not to be an amphibole.ll A.N. Winchell l2also has discussed the application of Warren’s formula to manyanalyses, with plots of the optical data. V. E. Barnes l3 shows thatgreen hornblende is converted into the “ basaltic ” variety byheating in air ; iron is essential to the change ; in hydrogen, greenhornblende is re-formed. Analyses of both varieties are given byT. 1~himura.l~ Formulae for the alkali amphiboles have beenproposed by H. Berman and E. S. Larsen,15 who deduce a limitedmiscibility. Lattice dimensions for the monoclinic amphiboleshave been determined by G. Greenwood and A. L. Parsons,16 andAmer. Min., 1931, 16, 411, 488; A., 1228.2.Krist., 1929, 70, 234; A., 1931, 595.Atti R. Accad. Lincei, 1931, [vi], 13, 705; A., 1931, 1391.H. O’Daniel, 2. Krist., 1930, 75, 575; A., 1931, 594.Jahrb. Min., Be&-Bd., 1931, [A], 64, 217; A., 494.Amer. Min., 1931, 16, 195; A., 494.Jap. J . Geol. Geog., 1932, 10, 67.lo Jahrb. Min., Bed.-Bd., 1930, [A], 60, 171; A., 1931, 595.loa Amer. J. Sci., 1931, [v], 22, 203; A., 1931, 446.l2 Amer. Min., 1931, 16, 250.l3 Ibid., 1930, 15, 393; A., 1931, 818.l4 Min. Mag., 1931, 22, 561; A., 1931, 1390.l5 Amer. Min., 1931, 16, 140; A., 38.lG Univ. Toronto Stud. Qeol., 1931, No. 30, 29; A., 493.l1 Ibid., p. 193HALLIMONI). 291analyses have been given for tremolite by A. L. Coul~on,~~ forbabingtonite by C. Palache and F.A. Gonyer,ls for hornblende byH. Heritsch,lg and for manganese-rich ferroanthophyllite by A.Orlov.20 Grunerite from Pierrefitte is described by H. V. Warren,21and N. Sundius 22 has discussed various grunerites, with analysesand optical properties, with respect to their manganese content.Veins of nephrite after pyroxene are described by H. Rose and J.Ilir~mme,~~ and specimens of various " jade " minerals (previouslyidentified mineralogically) have been tested by X-ray methods byP. L. Mer15tt.~~Micas, etc.-Fuchsite with 2.740/, Cr203 has been analysed byS. K. Chatterjee; 25 H. Meixner 26 has tested the various methodsfor determining chromium in mica, and finds earlier methods werenot reliable. A very important source of error in micas may be theomission to separate the rarer alkali metals; F.L. Hess and J. J.Fahey 27 have found 3.14% of caesium oxide in a biotite. J. Jakob 28continues his studies with several analyses of biotites and phlogo-pite; he considers that Ti never replaces Al or Si, but always 2Mg;apparently lime is again completely absent from these micas.F. C. Phillips 29 describes a margarite in which much of the lime hasbeen replaced by soda. Chlorites have been analysed by A. Goos-sens,30 S. Pavlovitch31 (from corundum rocks), and S. K ~ z i k ~ ~(from Tatra granite) ; also by G. L. D ~ c h a n g , ~ ~ who interprets 8 newanalyses as mixtures of serpentine, amesite, etc. J. Orcela foundfor ripidolite heated in nitrogen a sharp maximum at 780" due to2FeO + H20 = Fe,03 + H2.Chamosite, the chlorite of the ironores, was early obtained from Schmiedefeld ; the present generallyaccepted formula rests upon analyses of better material ; H. Jung 35has separated chamosite from this ore and obtains the formula5Al,0,,15R0,11Si02,16H,0, the accepted ratios being 5 : 15 : 10.l7 Rec. Geol. Surv. India, 1931, 63, 444; A., 1931, 595.l9 Centr. Min., 1931, 364.21 Min. Mag., 1931, a2, 477; A., 1931, 595.22 Amer. J . Sci., 1931, [v], 21, 330; A., 1228.23 Centr. Min., 1932, 301.25 Rec. Geol. Surv. India, 1932, 65, 536; A . , 1107.2 6 Centr. Min., 1931, 318.28 2. KriBt., 1932, 82, 271; A . , 715.29 Min. Mag., 1931, 22, 482; A., 1931, 595.30 Natuurwetensch. Tijds., 1931, 13, 119; A., 1931, 817.31 Bull. SOC. franc.Min., 1930, 53, 535.32 Bull. A d . Polonake, 1930, [A.], 536; A., 1931, 706.3a Chem. Erde, 1931,8, 416; A . , 1931, 1030.34 Bull. SOC. franc. Min., 1930, 52, 194; A . , 1931, 594.Chem. Erde, 1931, 8, 275; A., 1931, 1030.Amer. Min., 1932, 17, 295.2o Ibicl., 1932, 269.24 Amer. Min., 1932, 17, 497.27 Amer. Min., 1932, 17, 173; A., 1228292 GEOCHEMISTRY.X-Ray patterns distinguish it from thuringite. J. P. Arend36gives analyses of ooliths and gangue in the Lorraine ores.Felqmrs.-Methods for the identification of the felspars are de-scribed in detail by K. Chudoba, " Felspate 11. ihre prakt. Bestim-mung " (Stuttgart, 1932)) and H. Ebert 37 discusses the determinationof acid plagioclases. Anorthoclase from an Icelandic lava isdescribed by L.Hawkes and H. F. Harwood; 38 the surroundingglass must have uiidergone a subsequent change in composition withincrease in sodium oxide. Certain felspars apparently deviatefrom t'he standard formula; I). S. B e l i a n k i ~ ~ , ~ ~ who has collectedpreliminary data, fails to confirm Jakob's negative results forCaO and Ba0. A. G. MacGregor 40 uses cloudiness in the felspars asa criterion for thermal metamorphism.Clays.-Kaolin has been synthesised by W. No11 41 by heating theprecipitate in a pressure bomb a t 300". H. Jung42 shows thatkaolin can be partly dehydrated reversibly, yielding an amorphousproduct up to 550" ; the heat of hydration in this reaction has beendetermined by E. Klever and E. K ~ r d e s . ~ ~ Kaolin in shales isattributed by J.Kuh144 to the action of sulphuric acid. Japaneseacid clays have been further studied by several workers : the X-raypatterns resemble those of fuller's earth, attributed to a commoncrystalline clay-mineral ; thermal dehydration shows rapid loss at70-260" and a t 450-700"; basic and acid dyes are adsorbed,especially after removal of acid-soluble aluminium and iron. P. P.Kerr 45 discusses the presence of montmorillonite. General dis-cussions on clay are given by P. Kastner and I?. K. &layer, c. E.Marshall, P. H. Norton and F. B. Hodgdon, and R. Bradfield.46Vanadium occurs iiz red clay from De~onshire,~~ while the asso-ciated nodules contain as much as 13.96% of V,05.Zeolites.-M. H. Hey 48 gives a general review of the literature onzeolites ; 16 thomsonites analysed by him 49 show both replacementsCaAl-NaSi and Ca-Na,.Dehvdration of heulandit'e is described36373839404 14243444.546474848vCompt. rend., 1032, 194, 736, 990; L4., 360, 493, 595.l'sch. min. petr. Mitt., 1931, 42, 8 ; A . , 1931, 1390.Min. Mag., 1932, 23, 163; A., 1015.Centr. Alin., 1931, 356.Min. Mag., 1931, 22, 524; A., 1931, 1039.Naturwiss., 1932, 20, 366; A., 716.Chem. Erde, 1932,7, 113; A., 596.Yer68. Kaiser WilhelnL-Inst. Silikatforsch., 1930, 3, 17.Bull. Acad. Polonaise, 1931, [ A ] , 665.Amer. Min., 1932, 17, 192; Econ. Geol., 1931, 26, 153; A., 1228.See Abstracts under these names.G. E. L. Carter, Min. Mag., 1931, 22, 609; A,, 1931, 1390.Ibid., 1930, 22, 422.Ibid., 1033, 23, 51; A , , 715HALLTMOND. 293by P.Gaubert,so and P. G. Bird 51 has shown that zeolites can bedehydrated by freezing. Base exchange is used by G. Austerweil 52as a means of purifying salt preparations; when the exchangeresults in an insoluble compound the whole of a salt such as Na,CrO,may be removed (by a zeolite containing lead). Base exchange inpermutite has been extensively studied by E. Gruner 53 and others.Phosphates.-The apatite minerals have a peculiarly variedcomposition : S. B. Hendricks, M. E. Jefferson, and K. M. Mosley 54have analysed a variety of products, partly synthetic, and concludethat F in fluorapatite can be replaced by CO,, OH, SO,, SiO,, 0,C1, Br, or I , yielding minerals such as voelkerite, staffelite, collo-phanite, etc.X-Ray photographs show that animal bone is acarbonate apatite, which gains fluorine on fossilisation. Turquoiseanalyses have been discussed by H. J ~ n g . ~ ~J. Lietz56 has compared the constants for various analysedminerals in the pyromorphite group ; the order is pyromorphite-mimetite-vanadinite. A Spanish vanadinite is described byF. M. Martin.57 Intensely blue wavellite 58 contains 0.5% Cr20,.Veszelyite from Moravia 59 apparently forms an isomorphous serieswith arakawite and kipushite; new crystals of the latter have beendetermined by H. Buttgenbach.60 Leucophosphite is a new hydrousphosphate of K, Fe,E. Dittler and H. Hueber 62 have aiialysed rnottramite fromBolivia, for which they obtain a general formula that also agreeswith the Otavi descloizite.Psittacinite 63 has the composition2Pb0,2CuO,V20,,2H2O. Fervanite 64 is 2Fez03,2V,0,,5H20.Arsenoklasite is a new manganese arsenate from LBngban.65Legrandite, a complex zinc arsenate, is described by J. Drugman,M. H. Hey, and F. A. T. L. Walker G7 gives analysesof triphylite with colunihite, from a pegmatite in Manitoba.5 0 Bull. SOC. franq. Min., 1030, 52, 162.53 Compt. rend., 1931, 193, 1013.54 Z. Krist., 1932, 81, 352; A . , 494.f i 6 2. Krist., 1931, 77, 437; A., 1931, 817.5 7 Anal, Fis. Quim., 1932, 30, 377 ; A . , 530.G 8 A. Orlov, 2. Krist., 1931, 77, 317; A . , 1931, 707.59 V. Zsivny, ibid., 1932, 82, 87; A . , 595.Bull. Acad. roy. Be@., 1931, [v], 18, 43; A , , 494.61 E. S. Simpson, J .Roy. SOC. I+'. Australia, 1931-1932, 18, 69.63 Tscli. min. petr. Mitt., 1931, 41, 173; A . , 1931, 707.63 S. Taber and W. T. Schaller, Amw. Min., 1930, 15, 575; A . , 1931, 517.64 F. L. Hess and E. P. Henderson, ibid., 1931, 16, 273; A . , 38.65 G. Aminoff, K. Svenska Vetenskaps Akad. Handl., 1931, [iii], 9, No.6 o Min. Mag., 1932, 23, 17.5; A., 1015.6 7 Univ. Toronto Stud. (Xeol., 1931, No. 30, 9 ; A . , 493.51 Ind. Eng. Chem., 1932,24, 793.2. anorg. Chew., 1932, 204, 321, etc.6 6 Chem. Erde, 1932, 7, 77; A . , 596.5, 52; A., 1931, 1028294 GEOCHEMISTRY.Xulphates, etc.-M. H. Hey 68 finds that pink specimens offauserite from Hungary are really epsomite, stained with cobalt ;cupriferous melanterite 69 occurred in an ancient stope in Cyprus.Natural ferrous sulphates are discussed by R.Scharizer,?O andartificial voltaites by B. Gossner and E. Fell.71 Pickeringite,a hydrous sulphate of aluminium and magnesium, is describedby R. L. R~therford.'~ Other analyses include krausite andcreedite ; 73 castanite from California 74 and from Chuquicamata ; 75roeblingite from Franklin Furnace ; 76 pi~keringite.'~ C. Kuzniar 78describes secondary deposits of Glauber's salt in potash-bearingsediments.New minerals include Letovicite, (NHq)3H(S04)2,79 in coal-mine dumps ; Schairerite, Na,SO,,Na(F,CI) ; 8o Ardealite,CaHP04,CaS0,,4H20 ; Klebelsbergite, a basic antimonysulphate; 82 Glaucocerinite, basic sulphate of Zn, Cu, Al; 83" Alkanasul, " sulphate of A1 and alkalis. 84Detailsof the recently discovered pitchblende-silver deposit a t Gt,.BearLake in Canada are given by D. F. Kidd.86 Manganese compoundsinclude b i ~ b y i t e , ~ ~ coronadite 88 and romanechite ; 89 the newmineral magnesiosussexite, 2(Mg,Mn) 0 ,B203,H20, isomorphous withcamsellite, occurs in veinlets in the Michigan hzematite.wCuprotungstite has been analysed by W. T. S ~ h a l l e r . ~ ~68 Min. Mag., 1931, 22, 510; A . , 1931, 1029.69 Ibid., 1930, 22, 413; A., 1931, 191.70 2. Kriat., 1930, 75, 67 ; A., 1931, 459.71 Ber., 1932, 65, [B], 393.72 Amer. Min., 1932, 17, 401.73 W. F. Foshag, ibid., 1931, 16, 352; 1932, 17, 75; A., 139.74 A. F. Rogers, ibid., 1931, 16, 396; A., 140.7 5 M. C. Bandy, ibid., 1932, 17, 534.7 6 R. Blix, ibid., 1931, 16, 455; A ., 1107.7 7 R. L. Rutherford, ibid., 1932, 17, 401.713 Bull, Acad. Polonaise, 1931, [ A ] , 411 ; A . , 714.7 9 J. Sekanina, 2. Krist,, 1932, 83, 177; A . , 1015.81 J. Schadler, ibid., 1932, 17, 251.W. F. Foshag, Amer. Min., 1931, 16, 133.V. Zsivny, Math. Nat. Anz. Ungar. A b d . IViss., 1929, 46, 19; Chent.Zentr., 1930, ii, 3530.83 E. Dittler and R. Koechlin, Centr. Min., 1932, 13.84 5. Westman, Bol. Min. SOC. nac. Min., 1931,43, 433 ; Chom. Zentr., 1932,8 6 Amer. Min., 1932, 17, 234; A . , 1228.86 Econ. Qeol., 1932, 27, 145.87 H. Corti, Anal. Asoc. Quim. Argentina, 1931, 19, 109 ; A., 140.i, 673.J. Orcd, Compt. rend., 1932, 194, 1956; A., 716.F. Zambonini and V. Caglioti, ibid., 1931, 192, 750; A., 1931, 707.J. W. Gruner, Amer. Min., 1932, 17, 509HALLIMOND.295Water, etc.K. Higashi, K. Nakamura, and R. Harag1 have determined thespecific gravity and vapour pressure of sea-water at various con-centrations between 0" and 175". Copper is found by electrolysisto be about 10 mg. per cu.m. ; 92 ammonia in sea-water varies between0 and 48 mg. per cu.m. a t the surface, up to 350 mg. at 25 m. depth.93R. Willstatter 94 attributes the blue colour to copper ammines.Hydrogen-ion studies have been made by D. Goulstong5 andT. G. Thompson and R. U. Bonnar.96 Off Brest the reducing powerfor potassium permanganate is found by P. Chauchardg7 to risesomewhat in stormy weather; below 100 m. depth it rapidlydiminishes. The silica content is discussed by H. M. King,98 andN. W.Rakestraw 99 has determined phosphate, nitrate, and nitritecontents near Cape Cod.Formaldehyde in rain water is attributed by N. R. Dhar andA. Ram to direct formation in ultra-violet light. C. Srikantiagives the combined nitrogen in rain water at Bangalore. Rainanalyses a t Geneva, N.Y., for a 10-year period have been recordedby R. C. Collison and J. E. Mensching.3 Waters from 80 Japaneselakes have been analysed by S. Yoshim~ra.~ A. H. Wiebe5 hasdiscussed the bearing of dissolved phosphorus and nitrogen in theMississippi upon the plankton. The relation of iodine contents togoitre has been further investigated by J. Kupzis; adequacy ofiodine supply can be ascertained from the amount excreted. Thedistribution of iodine in water and coal is described by R. Wache ; 'iodine is without effect as a fertiliser, but is assimilated.E. Schantl*records 0.015% of magnesium iodide in well waters from the E.Indies. Many spring waters have been analysed. Picon9 hasg1 J . Soc. Chem. Ind. Japan, 1931, 34, 7 2 ~ ; A., 1931, 1265.g2 W. R. G. Atkins, J . MarineBiol. ASSOC., 1932, 18, 193; A., 714.s3 H. R. Seiwell, Ecology, 1931, 12, 485; A., 1931, 1145.94 Natumuiss., 1930, 18, 868.95 J . Proc. Roy. SOC. N.S.W., 1931, 65, 43; A., 247.96 Ind. Eng. Chem. (Anal.), 1931, 3, 393; A., 1931, 1389.9 7 Compt. rend., 1932, 194, 1256; A., 594.98 Contr. Canadian Biol. Fish., 1931, 7, Nos. 8-11, D, Nos. 1-4, 129-137.Science, 1932, 75, 417; A., 594.Mysore Univ. J., 1930, 4, 195; A., 1931, 594.New York State Agric.Exp. Stu. Tech. Bull., 1932, No. 193; A., 829.P m . Imp. Acad. Tokyo, 1932, 8, 94; A., 594.Science, 1931, 73, 652; A,, 1931, 930.Latvij. Univ. Raksti, 1930, 1, 425; A., 1931, 331.Mitt. Lab. prews. geolog. Landesanst., 1931, No. 13,43; Chem. Zentr., 1931,Chem-Ztg., 1932,56, 341; R., 594.Compt. rend., 1932,194, 1175; A., 594.1 Nature, 1932,130, 313; A., 1106.ii, 981296 GEOCHEMISTRY.investigated the organic carbon content, which is not directlyrelated to the results with potassium permanganate. Electricalconductivity tests are discussed by P. S. Tutundgie,lo and byE. Bovalini and E. Vallesi,ll who find the method useful withincertain limits as a guide to the dissolved matter. Muds have beenstudied by D. M. Reid,12 H. B. Moore,13 and others, with referenceto pH and content of phosphate, oxygen, etc.Work on natural gasesincludes several discussions of the hydrocarbon contents ; kryptonand xenon are estimated by N. P. Pentchev l4 in several Bulgarianga,ses.Soils.Soilcolours have been classified by N. A. Archangelskaya,16 usingOstwald's colour disc. There are numerous papers describing soilvarieties, which it is only possible to summarise in brief. Specialsoils result from the weathering of volcanic tuffs, loess and laterite ;in other cases vegetable decay products are dominant, forming peaty,pine, and other special types. Several soil surveys are recorded fromAustralia, the Nile, and Eastern Europe.H. Keller15 describes methods of soil charting in U.S.A.Coal.A.Duparque l7 considers that most coking coals are producedfrom lignin, bituminous coals from cutin ; anthracites belonging tothe latter class differ from the others. R. Lieske and K. Winzer l8also support the lignin theory, and G. Stadnikow l9 finds well-preserved lignin in shale. On the other hand, P. Krassa20 findsthat in fungal decomposition of wood, lignin is destroyed. Theaction of bacteria on cellulose is discussed by F. Fischer 21 and S. A.Waksman,22 while specific organisms in coal are described by R.L i e ~ k e . ~ ~ Base exchange involving the roof-clay has been suggestedas affecting the seams, but this is discounted by W. H. A. Pen~eler.~*lo Bull. Xoc. chiin. Yougoslav., 1931, 2, 77; 1932, 3, 33; A., 829.l1 Ann. Chim. Appl., 1931, 21, 51; A., 1931, 458.l2 J.Marine Biol. ASSOC., 1932, 18, 299; A., 714.l3 Ibid., 1931, 17, 325; A., 1931, 930.l4 Compt. rend., 1931, 192, 691; A., 1931, 594.l5 2. Pflanx. Diing., 1932, 24, A., 38.l6 Trans. Dokuchaiev Soil Inst., 1932, 6, 197; A., 110s.l7 Comnpt. rend., 1931, 192, 1472, 1257.Brennstoff-Chem., 1931, 12, 205; A., 1931, 931.l9 Ibid., 1932, 13, 547; A., 1015.2o Angew. Chem., 1932, 45, 21; A., 360.21 Proc. 111 Int. Conf. Bit. Coal, 1932, 2, 809; A., 1107.22 Brwmstoff-Chem., 1932, 13, 241 : A., 1016.2 3 Ges. Abhandl. liennt. h'ohle, 1930, 9, 27 ; A., 350.24 N.Z. J. Sci. Tech., 1931, 12, 284; A., 1931, 951, 1030HALLIMOND . 297A critical review of the published theories of coal formation is givenby E. Bed, A. Schmidt, and H.K o ~ h . ~ ~Petroleurn is regarded by A. I?. von Stah126 as related to theoccurrence of hydrogen sulphide springs, which are attributed tothe decomposition of proteins. K. Kobayashi 27 assigns the originof Japanese petroleum to the distillation of buried fish remains byvolcanic action under the sea, followed by absorption in acid clays.Chemical aspects of petroleum formation have been discussed byS. C. Lind.2*Contributions to the description of coal have been made by H.B r i g g ~ , ~ ~ who finds a graphical relation between the oxygen andcarbon contents of fusain, etc. Resin in coals is described by K. A.Jurasky 30 and H. Steinbrecher ; 3l E. Hoffmann and H. Kirchberg 32give a detailed account of resin inclusions in a Ruhr coal. Browncoals containing fibrous lignite, residues of the bark of conifers, aredescribed by' W. Gothan and Benade.33 Contrary to views expressedby E. Berl and others (above), G. Stadnikow3* describes a Siberiancoal seam, free from metamorphism, in which the upper layers aretypical brown coals, the lower being bituminous, suggesting thetransformation of brown coal into bituminous.Meteorites.Small pieces of siliceous glass known as tektites have been foundin Indo-China, Malay, North Borneo, and the Philippines; thecomposition is remarkably uniform, with about SiO,, 70 ; A1203, 12 ;FeO, 5% etc., and they are believed by A. Lacroix 35 to be of meteoricorigin. A. R. Alderman36 has described meteor craters fromHenbury, Australia; glassy fused rock was found, with largenumbers of iron fragments. Among meteorites recently describedmay be mentioned an iron meteorite from containing over16% of nickel, an amount also found in the Hoba (Grootfontein)25 Angew. Ghem., 1932, 45, 517 ; A., 1016.z G Petroleum, 1931, 8, 145; A., 1931, 460.2 7 J . SOC. Chenz. I n d . Japan, 1931, 34, 102.z 8 Science, 1931, 73, 19; A., 1931, 332.2Q Proc. Roy. SOC. Edin., 1932, 52, 195; A., 716.3o Brennstoff-Chem., 1931, 12, 161 ; A., 1931, 515.31 Ibid., 1931, 12, 163; -4., 1931, 818.32 Ibid., 1930, 11, 389.33 Braunkohle, 1930, 29, 274; A., 1931, 60.34 Brennstoff-Chem., 1932,13, 101 ; A., 597.35 Compt. rend., 1930, 191, 893; 1931, 192, 265, 1685; A . , 1931, 1146;3G Min. Mag., 1932, 23, 19.38 Amer. J . Sci., 1931, [v], 22, 360.1932, 1028.K 298 GEOCHEMISTRY.meteorite,39 which is the largest known. Other irons are describedby H. H. Nininge~-,~* L. L. F e r m ~ r , ~ l C. Palache and F. H.G ~ n y e r , ~ ~ D. R. Grantham and F. O a t e ~ . ~ ~A. R. Crook and 0. C. Farrington 44 describe a meteorite with high(Fe,Mg)O. A pallasite from Central Australia 45 contains fragmentalolivine ; E. S. Simpson and D. G. Murray 46 describe a siderolitecontaining large crystals of dark olivine and greyish-white enstatite.A fragment from S. E. Arabia described by W. Campbell Smith 47has the same minerals in choiidrules with some glass and felspar ; ina special method of analysis by M. H. Hey the metals are separatedby heating the powder in a current of dried chlorine.A. F. HALLIMOND.39 L. J. Spencer, Min. Mag., 1932,23, 1; A., 369; also S. G. Gordon, Yroc.40 Amer. J . Sci., 1931, [v], 22, 69; Aneer. Min., 1932, 17, 221, 396; S.,41 Rec. Geol. Survey India, 1931, 65, 161 ; A., 1931, 1265.42 Amer. Min., 1932, 17, 357.43 Min. Mag., 1931, 22, 487; A., 1931, 1028.44 Trans. Ill. Acad. Sci,, 1930, 22, 442; A., 1931, 1389.4 5 L. J. Spencer, Min. Mag., 1932,23, 38; A., 359.c6 Ibid., p. 33 ; A . , 359.4 7 Ibid., p. 43 ; A., 359.Acad. Nat. Sci. Philadelphia, 1931, 83, 251.1230