American Mineralogist. Volume 71, pages 1277-1282. 1986 NEW MINERAL NAMES* FRANK C. HAWTHORNE, MICHAEL FLEISCHER, EDWARD S. GREW, JOEL D. GRICE, JOHN L. JAMBOR, JACEK PuZIEWICZ, ANDREWC. ROBERTS, DAVIDA. VANKO,JANET A. ZILCZER Bastnaesite group minerals mineralization within alluvial deposits, found in the Aldan shield and in Kamchatka, eastern USSR. Other associated mineral in- Z. Maksimovic, Gy. Panto (1983) Mineralogy of yttrium and clusions are cuprorhodsite, malanite, native Os, iridosmine, lau- lanthanide elements in karstic bauxite deposits. Trav. Comite rite, erlichmanite, cooperite, sperrylite, chalcopyrite, and bornite. Internatl. Etude Bauxites, Alumine, et Aluminum, 13, 191- 200 (in English). No cleavage. Color is iron black, metallic luster, gray in reflected light. Microhardness is 578 ::t 140 kglmm2, with 30-g load. Very Electron-microprobe analyses are given of secondary phos- brittle. Reflectancesare [nm(%)] 460(35.0-37.5), 480(34.4-37.2), phates from the lower parts of karstic bauxites from Hungary 500(34.0-37.1), 520(34.0-37.1), 540(33.6-37.2), 560(33.4-37.2), and Yugoslavia, including bastnaesite-(Ce), bastnaesite-(La), syn- 580(33.1-37.5), 600(32.8-37.7), 620(32.6-37.8), 640(32.4-37.8), chysite-(Nd), monazite-(Nd) (see Am. Mineral., 68, 849), neo- 660(32.2-37.8), 680(32.1-38.1), 700(32.0-38.4), 720(32.0-38.7), dymian goyazite, and two new members of the bastnaesite group. 740(32.0-38.8). The minerals occur as fine-grained fracture fillings. The analyses The name is for the chemical composition. Polished thin sec- ofhydroxyl-bastnaesite-(La) and hydroxyl-bastnaesite-(Nd), yield tions containing the mineral are at the Mining Museum, Len- the following calculated formulas (C02 and H20 calculated, not ingrad Mining Institute. D.A.V. determined). (LaO.51 Ceo.ol Pr o.ION do.37Smo.06EUo.02Gdo.03Cao.06) 1.12(C03) 1.00- (Fo.ll(OH)o.,,), Cuprorhodsite* (Lao..,Pro.12Ndo.49Smo.07EUo.03Gdo.02),.o.(C03), (Fo.I.(O H)0.57)' N.S. Rudashevskii, YU.P. Men'shikov, A.G. Mochalov, N.V. (Lao.30Ceo.osPro.08N do.37Smo.07Euo.03Gdo.osDy 0.01Er 0.01Y 0.08Cao.05)1.10- (CO 3)I.OO(F0.28(0 H)0.38)' Trubkin, N.!. Shumskaia, V.V. Zhdanov(1985)Cuprorhodsite CuRh2S. and cuproiridsite CuIr2S.-New natural thiospinels (Lao.2SCeO.03Pr 0.08N do.sl Smo.09Euo.02Gdo.05 Y 0.0.Cao.03) I.IO(C03) 1.00- of platinum elements. Zapiski Vses. Mineralog. Obshch., 114, (F0.17(OH)0.S2)' Discussion. The new varieties are referred to as bastnaesite- 187-195 (in Russian). (Nd), and bastnaesite-(La) in one place, and as hydroxyl-bast- Analysis of the mineral (one of ten given) by electron micro- naesite in another, within the paper. With the calculated values probe gave Rh 39.6, Ir 10.3, Pt 6.8, Cu 7.55, Fe 5.31, S 29.8, of C02 and H20, the first-given formula corresponds to hydroxyl- sum 99.36%, corresponding to (Cuo.51Feo.4I)(RhI.66Iro.23Pto.15)S., bastnaesite-(La), and the remaining three to hydroxyl-bastnaes- Ideally, CuRh2S.. The mineral is not corroded by warm aqua ite-(Nd). Complete analyses, X-ray data, and physical properties regia. are needed to validate these as species. M.F. X-ray study (powder method) shows the mineral to be cubic, space group Fd3m, a = 9.88(1) A, Z = 8, = 6.74. The strongest lines (18 given) are 3.00(100)(311); D"""2.480(70)(400); Cuproiridsite* 1.904(80)(333,511); 1.758(100)(440); 1.009(90)(844). N.S. Rudashevskii, YU.P. Men'shikov, A.G. Mochalov, N.V. The mineral occurs as small (to 300 ILm) inclusions in angular Trubkin, NJ. Shumskaia, V.V. Zhdanov (1985) Cuprorhodsite isoferroplatinum host grains that are, in turn, the result of Pt CuRh2S. and cuproiridsite CuIr 2S.- New natural thiospinels mineralization within alluvial deposits, found in the Aldan shield of platinum elements. Zapiski Vses. Mineralog. Obshch., 114, and in Kamchatka, eastern USSR. Other associated mineral in- 187-195 (in Russian). clusions are cuproiridsite, malanite, native Os, iridosmine, lau- rite, erlichmanite, cooperite, sperrylite, chalcopyrite, and bornite. Analysis of the mineral (one of 26 given) by electron micro- No cleavage. Color is iron black, metallic luster, gray in reflected probe gave Rh 6.05, Ir 48.9, Pt 10.5, Cu 7.41, Fe 3.17, Ni 0.27, light. Microhardness is 498 ::t 30 kglmm2, with a 50-g load. Very S 24.6, sum 100.9%, corresponding to (CUo.6IFeo.30Nio.02)(Rho31" brittle. Reflectances are [nm(%)] 460(35.6-39.5), 480(35.8-39.3), IrL33Pto.28)S., Ideally, CuIr2S.. The mineral is not corroded by 500(36.4-39.3), 520(36.6-39.2), 540(36.7-39.2), 560(36.8-39.1), warm aqua regia. 580(36.9-39.1), 600(37.0-39.1), 620(37.0-39.0), 640(37.0-38.9), X-ray study (powder method) shows the mineral to be cubic, 660(36.9-38.8), 680(36.8-38.8), 700(36.7-38.7), 720(36.6-38.6), space group Fd3m, a = 9.92(1) A, Z 8, 7.24. The 740(36.6-38.5). = D""" = strongest lines (20 given) are 3.00(100)(311); 2.489(90)(400); The name is for the chemical composition. Polished thin sec- 1.912(70)(333,511); 1.760(100)(440); 1.011(70)(844). tions containing the mineral are at the Mining Museum, Len- The mineral occurs as small (to 300 ILm) inclusions in angular ingrad Mining Institute. D.A.V. isoferroplatinum host grains that are, in turn, the result of Pt Imiterite* Minerals marked with asterisks were approved before pub- * lication by the Commission on New Minerals and Mineral Names J.-J. Guillou, J. Monthel, P. Picot, F. Pillard, J. Protas, J.-C. of the International Mineralogical Association. Samama (1985) Imiterite, Ag2HgS2,a new mineral species: 0003-004X/86/0910-1277$02.00 1277 1278 NEW MINERAL NAMES Properties and crystal structure. Bull. Mineral., 108, 457-464 540,76.1,76.1; 560,75.3,77.4; 580,74.3,78.4; 600,73.2,79.2; (in French). 620,72.0,79.7; 640,70.7,79.8; 660,69.5,79.9; 680,68.5,79.8; The average of20 electron-microprobe analyses gave Ag 42.89, 700,67.5,79.5; 720,66.5,79.2; 740,65.9,78.7%. Hg 42.64, S 13.34, total 98.87%, which yields the empirical for- The mineral forms prismatic crystals from 100 x 100-120 up mula AgI.91Hgl.02SZ.00' to 200 x 300 or 60 x 400 ILm,with cleavage parallel to {100}. A single-crystal, X-ray diffraction structure analysis shows the The name is for the locality. mineral to be monoclinic, space group P2/e, a = 4.039(1), b = Cupalite 8.0052(6), e = 6.580(1) A, (3 = 107.11(2), V = 203.3(1) A3, Z = 2, 7.85g1cm3. The refined structure (R Microprobe analyses (nine grains) gave Cu 59.9-61.7, AI 29.3- D"'le = = 0.035 for 552 independent observed reflections) shows S atoms having a dis- 30.4, Zn 7.66-9.35, sum 98.61-100.45%, with negative corre- torted hexagonal close packing with Hg linearly co-ordinated and lation between Cu and Zn, corresponding to (Cu,Zn)Al. Ag trigonal-planar co-ordinated. The strongest X-ray diffraction X-ray study (Debye-Scherrer method) showed the mineral to lines (23 given) are 4.88(30)(011), 3.466(50)(110,111), be orthorhombic, a = 6.95(1), b = 4.16(1), e = 10.04(1) A, Z = 3.138(30)(002), 2.768(100)(102,121), 2.746(100)(111), 10, D,,"c = 5.12. The X-ray pattern is similar to that of synthetic 2.461 (80)(022,031), 1.959(30)(132,21 I), 1.467(35)(142,202,024). CuAlz, which has a centered orthorhombic cell. The strongest Imiterite occurs as anhedral grains up to I mm, with VHNlOo X-ray reflections (seven given) are 5.07(10)(002), 4.12(8)(010), 3.59(2)(110). = 86. In reflected light, it is light gray, pleochroic from bluish to pinkish and strongly anisotropic from blue to red-brown. The Cupalite is opaque, steel yellow. Luster metallic. Hardness 272- 318 kglmmz (20- and 50-g load). reflectance values range from 38.3 and 33.4 for A = 440 nm to 27.4 and 25.3 for A = 800 nm. In reflected light, the mineral has very weak bireflectance from The new mineral is associated with chalcopyrite, sphalerite, light gray to gray; under crossed nichols, it is weakly anisotropic polybasite, galena, and arsenopyrite in the Imiter mine, Jbel from gray to dark gray. Reflectance measurements (Rm, %, 20 Sarhro, Anti-Atlas, Morocco. It derives its name from the mine nm steps from 440 to 740 nm): 66.8, 66.1, 65.3, 64.5, 63.7, 62.9, locality; type material, consisting of polished sections, is at the 62.1,61.3,60.4,59.7,58.9,58.2,57.7,57.2,56.9,56.5. Ecole des Mines de Paris and at the Bureau de Recherches Geo- The mineral occurs as myrmekitic and dendritic droplike grains logiques et Minieres a Orleans-la-Source. J.D.G. from I x 4 to 5 x 35 ILm within khatyrkite (first generation) and as rounded or irregular grains from I x 5 to lOx 20 ILm in cracks and interstices in khatyrkite (second generation; this is usually intergrown with unnamed zinc aluminides).