Handbook of Mineralogy The Handbook of Mineralogy series is a Five Volume set authored by John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, and Monte C. Nichols, and published by Mineral Data Publishing. Each mineral known at the time of publication occupies one page of the handbook. In 2001 the copyright for the Handbook of Mineralogy was given to the Mineralogical Society of America by Kenneth W. Bladh, Richard A. Bideaux, Elizabeth Anthony-Morton and Barbara G. Nichols and the remaining volumes were shipped to the MSA warehouse in Chantilly, VA. Along with the copyright, MSA was given pdf files of each page of the handbook. These are freely distributed to the public on this website. In 2002, the MSA council established an editorial office, headed by Dick Bideaux, for the purpose of updating and maintaining the mineral database of the Handbook of Mineralogy and to continue converting the text files to PDF files for on-line access through the MSA website. After Dick Bideaux's untimely death in 2004 the MSA council organized an editorial committee in 2006 headed by Frank Dudas (MIT) to complete the task. This website is being organized to that end. Ken Bladh (Wittenberg University), one of the original authors of the Handbook, was appointed Editor of the Handbook of Mineralogy database by MSA Council action in June 2010, after Frank Dudas was unable to continue in that role. Professor Bladh’s initial goal is to bring the online Handbook up to date by adding pdf pages for all new minerals approved by the IMA after the publication of each original Handbook volume. Revision of the Handbook to reflect all IMA approved changes in nomenclature and new mineral data will be undertaken after the new minerals project is completed. Cite the online version of the Handbook as: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, and Monte C. Nichols, Eds., Handbook of Mineralogy, Mineralogical Society of America, Chantilly, VA 20151-1110, USA. http://www.handbookofmineralogy.org/. Abelsonite C H N Ni 31 32 4 (cid:13)c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Triclinic. Point Group: 1 or 1. Small aggregates, to 1 cm, of thin laths or plates. Physical Properties: Cleavage: Probable on {111}. Hardness = <3 D(meas.) = 1.33–1.48 D(calc.) = 1.45 Optical Properties: Semitransparent. Color: Dark grayish purple, pale purplish red, reddish brown. Luster: Submetallic to adamantine. Optical Class: [Biaxial.] Absorption: Strong reddish brown to reddish black. α = n.d. β = n.d. γ = n.d. 2V(meas.)= n.d. Cell Data: Space Group: P1 or P1. a = 8.508(24) b = 11.185(27) c = 7.299(15) α=90◦51(15)0 β =114◦08(12)0 γ =79◦59(13)0 Z=1 X-ray Powder Pattern: Green River Formation, Utah, USA. 10.9 (100), 3.77 (80), 7.63 (50), 5.79 (40), 3.14 (40), 5.51 (35), 6.63 (30) Chemistry: (1) Green River Formation, Utah, USA; electron microprobe analysis gave Ni 11%–14%; based on mass spectroscopic and IR results, the composition conforms to nickel porphyrin. Occurrence: Of secondary origin on fracture surfaces in oil shale. Association: Albite, orthoclase, pyrite, quartz, mica, dolomite, analcime. Distribution: In the USA, in a drill core from Wosco, Big Pack Mountain Quadrangle, and several other localities in or near the Mahogany Zone, Green River Formation, Uintah Co., Utah, and in the Piceance Creek Basin, Rio Blanco Co., Colorado. Name: Honors Philip Hauge Abelson (1913– ), American organic geochemist, President of the Carnegie Institution of Washington, D.C., USA, and Editor of Science. Type Material: The Natural History Museum, London, England, 1979,135;National Museum of Natural History, Washington, D.C., USA, 143566,145712. References: (1) Milton, C., E.J. Dwornik, P.A. Estep-Barnes, R.B. Finkelman, A. Pabst, and S. Palmer (1978) Abelsonite, nickel porphyrin, a new mineral from the Green River Formation, Utah. Amer. Mineral., 63, 930–937. (2) Storm, C.B., J. Krane, T. Skjetne, N. Telnaes, J.F. Branthaver, and E.W. Baker (1984) The structure of abelsonite. Science, 223, 1075–1076. (3) Mason, G.M., L.G. Trudell, and J.F. Branthaver(1989) Review of the stratigraphic distribution and diagenetic history of abelsonite. Organic Geochemistry, 14, 585–594. All rights reserved. No part of this publication may be reproduced,stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing. Abernathyite K (UO ) (AsO ) 6H O 2 2 2 4 2• 2 (cid:13)c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Tetragonal. Point Group: 4/m 2/m 2/m. As thick tabular crystals, composed of {001} and {110}, to 3 mm. Physical Properties: Cleavage: Perfect on {001}. Tenacity: Brittle. Hardness = 2–3 D(meas.) = >3.32 D(calc.) = 3.572 Fluoresces yellow-green under LW and SW UV. Radioactive. Optical Properties: Transparent. Color: Yellow. Streak: Pale yellow. Luster: Weakly vitreous. Optical Class: Uniaxial (–), anomalously biaxial (–). Pleochroism: O = yellow; E = pale yellow to colorless. ω = 1.597–1.608 (cid:15)= 1.570(3) 2V(meas.)= ∼5◦ Cell Data: Space Group: P4/ncc. a= 7.176(8) c = 18.126(10) Z=4 X-ray Powder Pattern: Fuemrole No. 2 mine, Utah, USA. 9.14 (10b), 3.84 (8b), 3.34 (8), 5.63 (7), 3.59 (7), 2.79 (6b), 2.28 (6) Chemistry: (1) (2) UO 57.7 56.97 3 P O 1.5 2 5 As O 21.6 22.89 2 5 K O 9.5 9.38 2 H O+ 9.9 2 H O− 4.6 2 H O 10.76 2 Total 104.8 100.00 (1) Fuemrole No. 2 mine, Utah, USA; microchemical analysis, H O+ by loss on ignition; 2 corresponds to K (UO ) [(As P ) O ]•7.68H O. (2) K (UO ) (AsO ) •6H O; 1.94 2 1.92 1.79 0.21 Σ=2.00 4 2 2 2 2 4 2 2 6H O assigned from crystal-structure analysis. 2 Mineral Group: Meta-autunite group. Occurrence: A rare secondary mineral coating fractures in bleached asphaltic sandstone hosting a Colorado Plateau-type uranium deposit (Fuemrol No. 2 mine, Utah, USA). Association: Scorodite, zeunerite, heinrichite. Distribution: In the USA, found at the Fuemrole No. 2 mine, Temple Mountain, Emery Co., Utah; from Cave Hills and Slim Buttes, Harding Co., South Dakota; at the West mine, Saguache Co. and the Clyde Long property, San Juan Co., Colorado; from near Tuba City, Coconino Co., Arizona. In the Rivi´eral mine, Lod`eve, H´erault, France. At Sailauf, northeast of Aschaffenburg, Bavaria, Germany. Name: To honor Jess Abernathy, Moab, Utah, USA, mine owner who found the first specimens. Type Material: National Museum of Natural History, Washington, D.C., USA, 112650. References: (1) Thompson, M.E., B. Ingram and E.B. Gross (1956) Abernathyite, a new uranium mineral of the metatorbernite group. Amer. Mineral., 41, 82–90. (2) Frondel, C. (1958) Systematic mineralogy of uranium and thorium. U.S. Geol. Surv. Bull. 1064, 220–222. (3) Ross, M. and H.T. Evans, Jr. (1964) Studies of the torbernite minerals (I): The crystal structure of abernathyite and the structurally related compounds NH (UO AsO )•3H O and 4 2 4 2 K(H O)(UO AsO ) •6H O. Amer. Mineral., 49, 1578–1602. 3 2 4 2 2 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing. Abhurite Sn2+O Cl (OH) 21 6 16 14 (cid:13)c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Hexagonal. Point Group: 3 2/m, 3m, or 32. As thin, six-sided crystals, platy to tabular on (0001), showing {0115} and {0001}, to 2 mm; as cryptocrystalline crusts. Twinning: On {0001}. Physical Properties: Fracture: Hackly. Tenacity: Fragile [sic]. Hardness = 2 D(meas.) = 4.42 (synthetic). D(calc.) = 4.417 Optical Properties: Transparent. Color: Colorless. Streak: White. Luster: Opalescent. Optical Class: Uniaxial (+). ω = 2.06 (cid:15) = ∼2.11 2V(meas.) = Small, observed on strained plates. Cell Data: Space Group: R3m, R3m, or R32. a= 10.0175(3) c = 44.014(2) Z=3 X-ray Powder Pattern: Sharm Abhur Cove, Saudi Arabia. 2.5313(100), 2.8915(70), 4.139(50), 3.404(50), 2.8175(50), 3.271 (35), 3.244 (35) Chemistry: (1) (2) Sn 73.4 73.44 Cl 15.7 16.71 O 11.0 9.43 H 0.4 0.42 Total 100.5 100.00 (1) Sharm Abhur Cove, Saudi Arabia; Sn by wet chemical analysis, Cl by ion-specific electrode, O by neutron activation, H by CHN analyzer. (2) Sn O Cl (OH) . 21 6 16 14 Occurrence: In blisterlike protuberances on the surface of a tin ingot recovered from a ship wrecked possibly 100 years ago (Sharm Abhur cove, Saudi Arabia). Association: Romarchite, kutnohorite, aragonite. Distribution: From the cargo of a ship wrecked in a Red Sea cove known as Sharm Abhur, about 30 km north of Jiddah, Saudi Arabia. From the cargo of a ship wrecked off Hidra, Norway. From a ship wrecked about 30 km north-northwest of St. Ives, Cornwall, England. Name: For the Saudi Arabian locality at Sharm Abhur Cove. Type Material: Royal Ontario Museum, Toronto, Canada; National Museum of Natural History, Washington, D.C., USA, 162403. References: (1) Matzko, J.J., H.T. Evans, Jr., M.E. Mrose, and P. Aruscavage (1985) Abhurite, a new tin hydroxychloride mineral, and a comparative study with a synthetic basic tin chloride. Can. Mineral., 23, 233–240. (2) (1989) Amer. Mineral., 74, 500 (abs. ref. 1). (3) Von Schnering, H.G., R. Nesper, and H. Pelshenke (1981) Sn Cl (OH) O , das sogenannte basische 21 16 14 6 Zinn(II)-chlorid. Zeits. Naturforsch., 36b, 1551–1560(in German with English abs.). (4) Edwards, R., R.D. Gillard, and P.A. Williams (1992) The stabilities of secondary tin minerals: abhurite and its relationships to Sn(II) and Sn(IV) oxides and oxyhydroxides. Mineral. Mag., 56, 221–226. All rights reserved. No part of this publication may be reproduced,stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing. Abramovite Pb SnInBiS 2 7 - Crystal Data: Triclinic. Point Group: 1 . Crystals, lamellar, to 1 mm, striated slightly parallel to elongation. Twinning: Lamellar on {100}. Physical Properties: Cleavage: Perfect on {100}. Fracture: n.d. Tenacity: n.d.. Hardness = n.d. D(meas.) = n.d. D(calc.) = n.d. Optical Properties: Opaque. Color: Silver gray; white with yellowish gray tones in reflected light. Streak: Black. Luster: Metallic. Optical Class: n.d. Bireflectance: Weak. Anisotropism: Distinct. R -R : (400) 14.0–32.9, (470) 13.9–29.0, (550) 15.7–29.9, (590) 16.4–30.2, (650) 17.9–30.8, (700) 1 2 18.9–31.2 - Cell Data: Space Group: P1 . a = 23.4(3) b = 5.77(2) c = 5.83(1) α = 89.1(5)° β = 89.9(7)° γ = 91.5(7)° X-ray Powder Pattern: Kupol fumarole field, Kudryavy volcano, Kurile Islands, Russia. 3.90 (100), 3.84 (71), 5.90 (36), 2.921 (33), 3.166 (26), 2.040 (20), 2.186 (18) Chemistry: (1) S 20.66 Se 0.98 Cu 0.01 Cd 0.03 In 11.40 Sn 12.11 Pb 37.11 Bi 17.30 Total 99.60 (1) Kupol fumarole field, Kudryavy volcano, Iturup Island, Kurile Islands, Russia; average of 4 electron microprobe analyses, corresponding to Pb Sn In Bi (S Se ) . 1.92 1.09 1.06 0.89 6.90 0.13 Σ=7.03 Occurrence: A product of precipitation from fumarolic gases (600° C) in an active stratovolcano. Association: Pyrrhotite, pyrite, wurzite, galena, halite, sylvite, anhydrite. Distribution: Kupol fumarole field, Kudryavy volcano, Iturup Island, southern Kurile Islands, Russia. Name: Honors Russian mineralogist Dmitry Vadimovich Abramov (1963–) of the A.E. Fersman Museum, Russia. Type Material: A.E. Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow (catalog no. 3436/1). References: (1) Yudovskaya, M.A., N.V. Trubkin, E.V. Koporulina, D.I. Belakovsky, A.V. Mokhov, M.V. Kuznetsova, and T.I. Golovanova (2007) Abramovite, Pb SnInBiS , a new mineral 2 7 species from fumaroles of the Kudryavy Volcano, Kurile Islands, Russia. Zap. Ross. Mineral. Obshch., 136(5), 37–43 (in Russian, English abstract); (2008) Geol. Ore Dep., 50, 551–555 (in English). (2) (2009) Amer. Mineral., 94, 1075 (abs. ref. 1). Mineralogical Society of America Handbook of Mineralogy Revised 1/31/2011 Abswurmbachite (Cu;Mn2+)Mn3+SiO 6 12 c 2001 Mineral Data Publishing, version 1.2 ° Crystal Data: [Tetragonal] (by analogy to braunite). Point Group: [4=m 2=m 2=m:] Anhedral grains, to 50 ¹m. Physical Properties: Hardness = n.d. VHN = 870{950, average 920 (25 g load). D(meas.) = n.d. D(calc.) = 4.96 (synthetic). Optical Properties: Opaque. Color: Black; gray in re°ected light. Streak: Brownish black. Luster: Metallic. Anisotropism: Weak. Cell Data: Space Group: [I4 =acd:] a= 9.406(1) c = 18.546(3) Z=[8] 1 X-ray Powder Pattern: Synthetic (Cu Mn2+ ) Mn3+SiO : 0:98 0:02 §=1:00 6 12 2.702 (100), 1.6507 (30), 2.350 (15), 2.133 (15), 1.459 (14), 1.4016 (11), 1.6627 (10) Chemistry: (1) SiO 10.1 2 TiO 0.23 2 Al O 0.58 2 3 Fe O 4.7 2 3 Mn O 72.1 2 3 CuO 11.6 MgO <0.04 CaO 0.16 Total 99.47 (1) Evvia Island, Greece; by electron microprobe, corresponds to (Cu Mn2+ Ca ) 0:88 0:10 0:02 §=1:00 (Mn3+ Fe3+ Al Ti Cu ) Si O : 5:51 0:36 0:07 0:02 0:02 §=5:98 1:03 12 Polymorphism & Series: Forms a series with braunite. Occurrence: In very low-grade, high-pressure metamorphic Mn, Al-rich quartzites. Association: Quartz, shattuckite, tenorite, sursassite, piemontite, ardennite, rutile, hollandite, clinochlore. Distribution: At Mili, Evvia Island, and Apikia, Andros Island, Cyclades Islands, Greece. Name: To honor Dr. Irmgard Abs-Wurmbach (1938{ ), German mineralogist. Type Material: Institute for Mineralogy, Ruhr University, Bochum, Germany; National Museum of Natural History, Washington, D.C., USA. References: (1) Reinecke, T., E. Tillmanns, and H.-J. Bernhardt (1991) Abswurmbachite, Cu2+Mn3+[O =SiO ]; a new mineral of the braunite group: natural occurrence, synthesis, and 6 8 4 crystal structure. Neues Jahrb. Mineral., Abh., 163, 117{143. (2) (1992) Amer. Mineral., 77, 670 (abs. ref. 1). All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing. Acanthite Ag S 2 (cid:13)c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Monoclinic, pseudo-orthorhombic. Point Group: 2/m. Primary crystals are rare, prismatic to long prismatic, elongated along [001], to 2.5 cm, may be tubular; massive. Commonly paramorphic after the cubic high-temperature phase (“argentite”), of original cubic or octahedral habit, to 8 cm. Twinning: Polysynthetic on {111}, may be very complex due to inversion; contact on {101}. Physical Properties: Cleavage: Indistinct. Fracture: Uneven. Tenacity: Sectile. Hardness = 2.0–2.5 VHN = 21–25 (50 g load). D(meas.) = 7.20–7.22 D(calc.) = 7.24 Photosensitive. Optical Properties: Opaque. Color: Iron-black. Streak: Black. Luster: Metallic. Anisotropism: Weak. R: (400) 32.8, (420) 32.9, (440) 33.0, (460) 33.1, (480) 33.0, (500) 32.7, (520) 32.0, (540) 31.2, (560) 30.5, (580) 29.9, (600) 29.2, (620) 28.7, (640) 28.2, (660) 27.6, (680) 27.0, (700) 26.4 Cell Data: Space Group: P2 /n. a= 4.229 b = 6.931 c = 7.862 β =99.61◦ Z=4 1 X-ray Powder Pattern: Synthetic. 2.606 (100), 2.440(80), 2.383(75), 2.836(70), 2.583(70), 2.456 (70), 3.080 (60) Chemistry: (1) (2) (3) Ag 86.4 87.2 87.06 Cu 0.1 Se 1.6 S 12.0 12.6 12.94 Total 100.0 99.9 100.00 (1) Guanajuato, Mexico; by electron microprobe. (2) Santa Lucia mine, La Luz, Guanajuato, Mexico; by electron microprobe. (3) Ag S. 2 Polymorphism & Series: The high-temperature cubic form (“argentite”) inverts to acanthite at about 173 ◦C; below this temperature acanthite is the stable phase and forms directly. Occurrence: A common silver species in moderately low-temperature hydrothermal sulfide veins, and in zones of secondary enrichment. Association: Silver, pyrargyrite, proustite, polybasite, stephanite, aguilarite, galena, chalcopyrite, sphalerite, calcite, quartz. Distribution: Widespread in silver deposits. Localities for fine primary and paramorphic crystals include: from J´achymov(Joachimsthal), Czech Republic [TL]. In Germany, at Freiberg, Schneeberg, Annaberg, and Marienberg, Saxony; and from St. Andreasberg, Harz Mountains. In Mexico, large paramorphs from Arizpe, Sonora; in the Rayas and other mines at Guanajuato; and from many mines in Zacatecas, Chihuahua, etc. In the USA, at Butte, Silver Bow Co., Montana; Tonopah, Nye Co., and the Comstock Lode, Virginia City, Storey Co., Nevada. From various mines at Cobalt, Ontario, Canada. At Chan˜arcillo, south of Copiapo´, Atacama, Chile. Name: From the Greek for thorn, in allusion to the shape of the crystals. Type Material: Emperor’s collection, Vienna, Austria, 2592. References: (1) Palache, C., H. Berman, and C. Frondel (1944) Dana’s system of mineralogy, (7th edition), v. I, 191–192(acanthite), 176–178(“argentite”). (2) Frueh, A.J., Jr. (1958) The crystallographyof silver sulfide, Ag S. Zeits. Krist., 110, 136–144. (3) Sadanaga, R. and S. Sueno 2 (1967) X-ray study on the α–β transition of Ag S. Mineral. J. (Japan), 5, 124–143. (4) Petruk, 2 W., D.R. Owens, J.M. Stewart, and E.J. Murray (1974) Observations on acanthite, aguilarite and naumannite. Can. Mineral., 12, 365–369. (5) (1960) NBS Circ. 539, 10, 51. (6) Criddle, A.J. and C.J. Stanley, Eds. (1993) Quantitative data file for ore minerals, 3rd ed. Chapman & Hall, London, 1. All rights reserved. No part of this publication may be reproduced,stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing. Acetamide CH CONH 3 2 (cid:13)c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Hexagonal. Point Group: 3m. Crystals are prismatic, to 5 mm, with prominent {1120}; as small stalactites and in granular aggregates. Physical Properties: Fracture: Fine conchoidal. Hardness = 1–1.5 D(meas.) = 1.17 D(calc.) = 1.15 Soluble in H O, taste very bitter; volatilizes on exposure to air and sunlight. 2 Optical Properties: Transparent. Color: Colorless, gray if included with carbonaceous material. Luster: Vitreous to greasy. Optical Class: Uniaxial (–). ω = 1.495(2) (cid:15)= 1.460(2) Cell Data: Space Group: R3c (synthetic). a= 11.44(3) c = 13.50(3) Z=18 X-ray Powder Pattern: Chervonograd,Ukraine. 5.7 (100), 3.54 (91), 2.86 (78), 3.32 (30), 2.17 (14), 3.98 (9), 3.83 (9) Chemistry: (1) Chervonograd, Ukraine; yields a positive qualitative test for NH ; identification 3 depends on close agreement of its X-ray powder pattern with that of synthetic acetamide. Occurrence: In burning waste coal heaps, formed between 50 ◦C and 150 ◦C. Association: Sal ammoniac (Chervonograd, Ukraine). Distribution: From near Chervonograd,L’vov-Volyn’ coal basin, Ukraine. At Shamokin, near Burnside, Northumberland Co., Pennsylvania, USA. Name: For ACETic acid and AMIDE, for ammonia in its composition. Type Material: Mining Museum, St. Petersburg Mining Institute, St. Petersburg, 1086/1; A.E. Fersman Mineralogical Museum, Academy of Sciences, Moscow, Russia, 77109. References: (1) Srebrodol’skii, B.I. (1975) Acetamide CH CONH – a new mineral. Zap. Vses. 3 2 Mineral. Obshch., 104, 326–328(in Russian). (2) (1976) Amer. Mineral., 61, 338 (abs. ref. 1). (3) (1976) Mineral. Abs., 27, 80 (abs. ref. 1). (4) Srebrodol’skii, B.I. (1986) Phases of mineral formation on spoil heaps of coal mines. Doklady Acad. Nauk SSSR, 290, 173–174(in Russian). (5) Jeffrey, G.A., J.R. Ruble, R.K. McMullan, D.J. DeFrees, J.S. Binkley, and J.A. Pople (1980) Neutron diffraction at 23 K and ab initio molecular-orbital studies of the molecular structure of acetamide. Acta Cryst., 36, 2292–2299. (6) Pekov, I.V. (1998) Minerals first discovered on the territory of the former Soviet Union. Ocean Pictures, Moscow, 19. All rights reserved. No part of this publication may be reproduced,stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing. Actinolite Ca (Mg;Fe2+) Si O (OH) 2 5 8 22 2 c 2001 Mineral Data Publishing, version 1.2 ° Crystal Data: Monoclinic. Point Group: 2=m: As bladed crystals, to 15 cm; columnar, may be kinked or bent; radiating ¯brous to asbestiform; granular to massive. Twinning: Simple or lamellar, common 100 ; lamellar, less common 001 . k f g k f g Physical Properties: Cleavage: Good on 110 , with intersections of 56 and 124 ; parting ± ± f g on 100 . Tenacity: Brittle, tough in ¯brous aggregates (\nephrite jade"). Hardness = 5{6 f g D(meas.) = 3.03{3.24 D(calc.) = [3.07] Optical Properties: Transparent to translucent. Color: Bright green to grayish green; in thin section, colorless, pale green to deep green. Streak: White. Luster: Vitreous, silky. Optical Class: Biaxial ({). Pleochroism: Weak; X = pale yellow, yellowish green; Y = pale yellow-green, green; Z = pale green, deep greenish blue. Orientation: Y = b; Z c = ^ 14 {18.5 . Dispersion: r < v; weak. ® = 1.613{1.646 ¯ = 1.624{1.656 ° = 1.636{1.666 ± ± 2V(meas.)= 79 {86 ± ± Cell Data: Space Group: C2=m: a = 9.891(1) b = 18.200(1) c = 5.305(1) ¯ =104:64(1) Z=2 ± X-ray Powder Pattern: Sobotin, Czech Republic. (ICDD 25-157). 2.719 (100), 2.543 (100), 3.401 (80), 8.47 (70), 4.91 (70), 3.143 (70), 2.959 (70) Chemistry: (1) (1) SiO 55.17 MnO 0.18 2 TiO 0.17 MgO 16.21 2 Al O 2.69 CaO 12.08 2 3 FeO 11.07 Na O 0.82 2 Total 98.39 (1) Southeast Anglesey, Wales; by electron microprobe, corresponding to (Ca Na ) 1:83 0:22 §=2:05 (Mg Fe2+ Al Fe3+ Mn Ti ) (Si Al ) O (OH) : 3:41 1:26 0:23 0:05 0:02 0:02 §=4:99 7:79 0:21 §=8:00 22 2 Polymorphism & Series: Forms a series with tremolite and ferro-actinolite. Mineral Group: Amphibole (calcic) group: 0.5 Mg=(Mg+Fe2+) 0.89; (Na+K) <0.5; · · A Na <0.67; (Ca+Na) 1.34; Si 7.5. B B ¸ ¸ Occurrence: Produced by low-grade regional or contact metamorphism of magnesium carbonate, ma¯c, or ultrama¯c rocks; also in glaucophane-bearing blueschists. Association: Talc, epidote, chlorite, glaucophane, pumpellyite, lawsonite, albite. Distribution: Many localities. In Austria, on Mt. Greiner, Zillertal, and at Untersulzbachtal. From Zermatt, Valais, Switzerland. At Snarum and Arendal, Norway. From the Ural Mountains, Russia. In the USA, from Gouverneur, St. Lawrence Co., New York; Franklin and Newton, Sussex Co., New Jersey; Chester, Windsor Co., Vermont; in the Fairfax quarry, Centreville, Fairfax Co., Virginia; Crestmore, Riverside Co., California; at Salida, Cha®ee Co., Colorado. \Nephrite jade" occurs, in the USA, south and east of Lander, Fremont Co., Wyoming; north from Cape San Martin, Monterey Co., California; and around Jade Mountain, near the Kobuk River, Alaska. Along the Fraser River, British Columbia, Canada. Around Mt. Cook, South Island, New Zealand. Fine material from the Kunlun Mountains, Sinkiang Uighur Autonomous Region, China. Name: From the Greek for ray, in allusion to the mineral's common radiating ¯brous habit. References: (1) Dana, E.S. (1892) Dana's system of mineralogy, (6th edition), 389{391. (2) Deer, W.A., R.A. Howie, and J. Zussman (1963) Rock-forming minerals, v. 2, chain silicates, 249{262. (3) Mitchell, J.T., F.D. Bloss, and G.V. Gibbs (1971) Examination of the actinolite structure and four other C2/m amphiboles in terms of double bonding. Zeits. Krist., 133, 273{300. (4) Gibbons, W. and M. Gyopari (1986) A greenschist protolith for blueschist in Anglesey, U.K. In: B.W. Evans and E.H. Brown, Eds., Blueschists and eclogites, Geol. Soc. Amer. Memoir 164, 217{228. (5) Phillips, W.R. and D.T. Gri®en (1981) Optical mineralogy, 229{231. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing. Acuminite SrAlF (OH) H O 4 • 2 (cid:13)c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Monoclinic. Point Group: 2/m or m. As acute dipyramidal crystals, showing {110}, {111}, and rare {112}, resembling spearheads, to 1 mm; in groups of crystals. Twinning: On {100}, as contact twins. Physical Properties: Cleavage: {001}, perfect. Hardness = 3.5 D(meas.) = 3.295(10) D(calc.) = 3.305(5) Becomes yellow on exposure to X-rays. Optical Properties: Transparent, yellowish if coated by “limonite”. Color: Colorless, white. Optical Class: Biaxial (+). Orientation: X = b; Y ∧ c = 15(1)◦. Dispersion: r > v, strong. α= 1.4507(3) β = 1.4528(3) γ = 1.4624(3)–1.4627(3) 2V(meas.)= 46◦–57◦ Cell Data: Space Group: C2/c or Cc. a = 13.223(1) b = 5.175(1) c = 14.251(1) β =111.61(2)◦ Z=8 X-ray Powder Pattern: Ivigtut, Greenland. 4.767 (10), 4.706 (10), 3.505 (10), 3.353 (10), 2.075 (9), 3.310 (8), 3.286 (8) Chemistry: (1) (2) Ca 0.02 Sr 37.04 38.84 Al 11.86 11.96 F 33.52 33.68 OH [6.82] 7.54 H O [7.80] 7.98 2 Total [97.06] 100.00 (1) Ivigtut, Greenland; by AA, Al by CDTA, F by electrolysis; OH calculated from charge balance, H O from theory; corresponds to Sr Al F (OH) •1.00H O. 2 0.98 1.02 4.07 0.93 2 (2) SrAlF (OH)•H O. 4 2 Polymorphism & Series: Dimorphous with tikhonenkovite. Occurrence: In a small cavity in a specimen from a strontium-rich portion of a cryolite deposit. Association: Fluorite, jarlite, thomsenolite, pachnolite, ralstonite, gearksutite, celestine. Distribution: In the Ivigtut cryolite deposit, southwestern Greenland. Name: From the Latin acuminis, sharp point, for spear head, the characteristic shape of the crystals. Type Material: University of Copenhagen, Copenhagen, Denmark. References: (1) Pauly, H. and O.V. Petersen (1987) Acuminite, a new Sr-fluoride from Ivigtut, South Greenland. Neues Jahrb. Mineral., Monatsh., 502–514. (2) (1988) Amer. Mineral., 73, 1492 (abs. ref. 1). (3) Krogh Andersen, E., G. Ploug-Sørensen,and E. Leonardsen (1991) The structure of acuminite, a strontium aluminium fluoride mineral. Zeits. Krist., 194, 221–227. All rights reserved. No part of this publication may be reproduced,stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of Mineral Data Publishing.