American Mineralogist, Volume 71, pages 1543-1548,1986 NEW MINERAL NAMES* FRANK C. HAWTHORNE, KENNETH W. BLADH, ERNST A. J. BURKE, T. SCOTT ERCIT, EDWARD S. GREW, JOEL D. GRICE, JACEK PuZIEWICZ, ANDREW C. ROBERTS, ROBERT A. SCHEDLER, JAMES E. SHIGLEY Bayankbanite somewhat higher reflectance than neltnerite, and a slightly more yellowish color compared to the bluish color of neltnerite. V.I. Vasil'ev (1984) New mercury minerals and mercury-con- Discussion. The name braunite II was first used (without ap- taining deposits and their parageneses. Trudy Inst. Geol. Geo- proval of the IMA-CNMMN) by De Villiers and Herbstein [(1967), fiz., Siber. Otdel. Akad. NaukSSSR, no. 587,5-21 (in Russian). Am. Mineral., 52, 20-40] for material previously described by Microprobe analyses (3 grains) gave Cu 43.0-59.0, Hg 20.9- De Villiers [(1946), Geol. Soc. S. Afr. Trans., 48,17-25] asferrian 40.9, S 17.0-18.7. HN03 induces pale-olive tint on surfaces per- braunite. This phase (from several mines in the Kalahari man- pendicular to longer axis, no reaction with NH03 on surfaces ganese field, South Africa) differed chemically from braunite parallel to it. No reaction with HCI and KOH. (Mn+2Mnt3Si012) by its lower Si content (4.4 wt% Si02) and by X-ray powder study of impure material yields 17 lines; the the presence of 4.3 wt% CaO. Crystallographically, both braunite strongest are 4.64(3), 2.74(4), 2.65(5), 1.983(3), 1.685(3). and braunite II have the same space group 14/acd, but braunite In reflected light white, strongly anisotropic with effects from II has a c cell parameter twice that of braunite. The refinement pale brown to bluish gray, strong bireflectance with slight creamy- of the crystal structures of braunite and braunite II by De Villiers pink tint (R,). No internal reflections. Some grains are tabularly [(1975), Am. Mineral., 60, 1098-1104], Moore and Araki [(1976), twinned. Am. Mineral., 61,1226-1240] and De Villiers [(1980), Am. Min- The mineral forms single, cataclased and corroded irregular or eral., 65, 756-765] and the description ofneltnerite by Baudrac- elongated grains or their intergrowths with cinnabar, chalcocite, co-Gritti et al. [(1982), Bull. Mineral., 105, 161-165] have shown and digenite. Transversal sections are hexagonal. Black. Streak that the structures of minerals and! or phases of the braunite group black. Luster metallic. Brittle, easily polishes. Hardness (Mohs') consist of different stacking sequences of three different layers: 3-3.5. A = (Mn+3,Fe+3).OI2'B = Mni2Mn:3Si2012 and B' = Ca2Mn:3- The mineral occurs in fluorite deposits at Idermeg-Bayan-Khan- Si2012' Neltnerite is (A + B') and has the formula Ca2Mni23Si2024, Ula (Mongolia). and braunite II is (3A + B'), which is CaMn143Si024 (hence the The name is for the locality. doubling of the c parameter). Both minerals have the same space Discussion. This may be two or three phases of composition group 14/acd. According to the Report of the IMA-IUCr Joint close to Cu.HgS" Cu6HgS4, or CUIOHg,S., as indicated by the Committee on Nomenclature [Bailey (1977) Am. Mineral., 62, author. Complete X-ray data needed. J.P. 411-415], neltnerite and braunite II have to be regarded as po- Iytypoids, the differences ofCa, Si, and Mn exceeding 0.25 atom per formula unit. The description of a new locality of braunite Braunite II II could serve as an occasion for the IMA-CNMMN to settle the nomenclature of this phase. E.A.J .B. C. Baudracco-Gritti (1985) Substitution du manganese bivalent par du calcium dans les mineraux du groupe: braunite, nelt- nerite, braunite II. Bulletin de Mineralogie, 108, 437-445 (in French). Canapbite* About 40 electron-microprobe analyses on material from a new D.R. Peacor, P.J. Dunn, W.B. Simmons, FJ. Wicks (1985) Can- locality (Tachgagalt, Anti-Atlas, Morocco) confirm the compo- aphite, a new sodium calcium phosphate hydrate from the sition of braunite II, previously only known from the Kalahari Paterson area, New Jersey. Mineralogical Record, 16, 467- (South Africa). 468. The ideal formula is Ca(Mn+3, Fe+3)14SiO,4;the Fe-free phase contains 4.6 wt% CaO and 4.9 wt% Si02. The results of the new Microprobe and DTA-TGanalysis gave Na20 16.5, MgO 0.2, analyses show a range of 4.6 to 6.1 wt% CaO and 4.8 to 7.6 wt% CaO 17.5, P20, 43.4, H20 21.8, sum 99.4%, corresponding to . Si02. These deviations from the ideal composition are tentatively Ca2.o,Na3.49Mgoo3H4.39(P04)4.01 5. 73H20, or, ideally Ca- explained by the possible existence of a solid-solution series be- Na2H2(P04)2.3H20 with Z = 2. tween braunite II and neltnerite (ideally CaMnt3Si012, with 9.5 X-ray studies show the mineral is monoclinic, space group Pa, wt% CaO and 10.2 wt% Si02). This series, however, cannot be cell dimensions a = 10.529 (5), b = 8.48 (I), c = 5.673 (4) A, complete because of the stable coexistence of the two minerals (3= 106.13 (6)°. The strongest lines (47 given) are: 8.47(80)(010), at Tachgagalt. Other asssociated minerals include marokite, haus- 5.44(80)(001), 4.36(70)(210, 201), 3.06(lOO)(3II, 211), mannite, crednerite, henritermierite, gaudefroyite, and calcite. 2.608(90)(321). Under the microscope, in reflected light, braunite II has a Canaphite occurs as colorless, transparent, prismatic, vitreous crystals, elongate on {00l}, tabular on {01O}, and composed of the forms {01O}, {OOI}, and {lOa}. The streak is white, and the Minerals marked with asterisks were approved before pub- cleavages are {a 1O}perfect, {lOa} poor, {a 1O}poor. Dme.. = 2.24, * lication by the Commission on New Minerals and Mineral Names Doak= 2.27. H = 2. Nonfluorescent. Optically biaxial negative, of the International Mineralogical Association. a = 1.496(2), (3 = 1.504(2), l' = 1.506(4), 2Vmeas= 52(5)", 2V_ = 0003-004X/86/l112-1543$02.00 1543 ,...- 1544 NEW MINERAL NAMES 52.9°. No observable pleochroism or dispersion. Orientation c = 12.42(4) A, a = 91.19(44)°, (3 = 99.94(82)°, l' = 98.64(47)° b, X /\ c Z = = 25°. V = 666.5 A' and Z = 1. The strongest lines (66 given) are: The mineral occurs as clusters of colorless crystals coating 12.41(70)(001),7.42(20)(010),6.95(50)(100),6.58(30)(101, 01 I), stilbite, purportedly from Haledon, New Jersey. The exact lo- 5.10(20)(102),4.31(40)(112),3.86(20)(103),3.46(20)(113), cality is unknown. 3.43(20)(121),3.16(100)(212,211,113),2.723(60)(123,023). The name is in allusion to the chemical composition, calcium Ehrleite occurs at the Tip Top mine, Custer, South Dakota as (Ca), sodium (Na), phosphate (P), and hydrogen (H). Type ma- vitreous, white to colorless, thick tabular crystals up to 2 x 2 x terial is in the Smithsonian Institution, Washington (no. 160286). 0.1 mm on a matrix of beryl and quartz, associated with mitri- A.C.R. datite, roscherite, hydroxyl-herderite, and goyazite-crandallite. Crystals show three pinacoids {l00}, {010} and {001} (assuming centrosymmetry), the habit form being chosen as {DOl}. Traces Cherepanovite* of parting are observed on (001), and the fracture is uneven to subconchoidal. Dme.. = 2.64(2), 2.62. H = 3112.The mineral N.S. Rudashevsky, A.G. Motshalov, N.V. Trubkin, N.M. Shum- Deal<= skaya, V.I. Shkursky, T.L. Evstigneeva (1985) Cherepanovite is nonfluorescent and soluble in cold 20% HCl. Optically biaxial positive, a 1.556(2), (3 1.560(1), 1.580(1), 2 Vme., = 62°, RhAs-A new mineral. Zapiski Vses. Mineralog. Obshch., 114, = = l' = 2 Veal<= 49°; Xllc, Y /\ b = 18° and Z /\ a = 9°. The name is for 464-469 (in Russian). Mr. Howard Ehrle, of Miles City, Montana, who found the ho- Microprobe analyses (16) gave Rh 54.6-57.9, Ru 0.82-2.14, lotype specimen. The holotype specimen is preserved in the col- Pt 0.08-0.94, Ir 0.00-0.17, Ni 0.09-0.34, As 40.6-43.0, average lection of the National Museum of Natural Sciences, Ottawa corresponding to RhAs. (NMNS no.49289). The cotype specimen is in the Museum of X-ray and electron-diffraction studies show the mineral to be Geology, South Dakota School of Mines and Technology, Rapid orthorhombic, a = 5.70 :t 0.02, b = 3.59 :t 0.01, c = 6.00 :t City, South Dakota (SDSM & T no. 2958). A.C.R. 0.01 A, Deal<9.72. Unit-cell parameters are almost identical to those of synthetic RhAs (space group Pnma, Z = 4). The strongest X-ray lines of the mineral (25 given) are 3.01(10)(002), Ertixiite* 2.10(6)(211), 1.771(2)(212), 1.501(2)(004), 1.354(2)(222)- the last Z. Rubo, H. Fengming, D. Chongliang (1985) Ertixiite-A new four broadened. mineral from the Altay Pegmatite Mine, Xinjiang, China. Geo- Brittle. Black when powdered. Coarse cleavage in one direc- chemistry (China), 4, 2,192-195. tion. In reflected light, well-pronounced orange tint. Anisotropic, green to dirty-brown anisotropic effects similar to those of mar- An average of six microprobe analyses gave SiO, 77.86, Na20 casite. No pleochroism, bireflectance almost not visible. Distinct 17.98, CaO 2.82, Al20, 1.45, FeO 0.04, sum 100.15%, corre- hardness anisotropy, H = 726-754 kg/mm' (50-g load). Reflec- sponding to the ideal chemical formula Na,Si409.