LauriteRuS2
c 2001-2005 Mineral Data Publishing, version 1

Crystal Data: Cubic. Point Group: 2/m 3. As octahedral, cubic, and pyritohedral crystals,
to 1 mm, and as rounded grains and inclusions in other minerals.
Physical Properties:
Cleavage: Perfect on {111}. Fracture: Subconchoidal. Tenacity: Verybrittle. Hardness = 7.5 VHN = 2760–2898, 2870 average (25 g load). D(meas.) = 6.43
D(calc.) = 6.39
Optical Properties: Opaque. Color: Iron-black, in polished section, white to gray, bluish.
Streak: Dark gray. Luster: Metallic.
R: (400) 51.2, (420) 49.8, (440) 48.5, (460) 47.0, (480) 45.7, (500) 44.6, (520) 43.7, (540) 42.8,(560) 42.0, (580) 41.3, (600) 40.6, (620) 40.1, (640) 39.5, (660) 39.0, (680) 38.5, (700) 38.1
Cell Data:

Space Group: P a3. a = 5.6135

Z=4

X-ray Powder Pattern: Borneo.
2.81 (vs), 3.29 (vs), 3.24 (s), 1.982 (s), 1.082 (s), 1.287 (ms), 1.256 (ms)Chemistry:
(1)
Ru
65.18
Os
[3.03]
IrCu

(2)
61.0
1.0(3)
46.1
12.7
5.30.1(4)
61.18

Compt. Rendus Acad. Sci. ParisS

31.79

38.0

Total [100.00]
100.0
99.6
100.00(1) Borneo; placer material; Os by difference. (2) Goodnews Bay, Alaska, USA; by electron
microprobe. (3) Rio Pilpe, Colombia; by electron microprobe. (4) RuS2 .
Polymorphism & Series:
Mineral Group:

Forms a series with erlichmanite.

Pyrite group.

Occurrence:

In ultramafic complexes and in placer deposits.

Association:
chromite.

Cooperite, braggite, sperrylite, other minerals of the platinum-group elements,Distribution: From placers in Borneo, as at Kalimantan (formerly Pontijn, Tanah Laut)[TL]. In South Africa, from the Merensky Reef of the Bushveld complex, at Potgietersrus; inthe Rustenburg and Union mines; also the Driekop and Onverwacht mines. In the USA, in the
Stillwater complex, Montana; on the Yuba River, Nevada Co., and from the Trinity River near
Douglas City, Trinity Co., California; at Goodnews Bay, Alaska. In Canada, in the Tulameen area,British Columbia. In Sierra Leone, from placers at Guma Water, and the Senduma chrome mines.
From the Konder massif, Aldan Shield, Sakha, Russia. In the Kapitanov chromite deposit, near
Zvenyhorodka, Ukraine. At Maud Creek, Howard River, New Zealand. Known in small amounts
from other localities.
Name: For Laura R. Joy, wife of Charles A. Joy, American chemist, Columbia University, NewYork City, USA.
Type Material:

University of Göttingen, Göttingen, Germany, 24541.

References: (1) Palache, C., H. Berman, and C. Frondel (1944) Dana’s system of mineralogy,(7th edition), v. I, 291–292. (2) Leonard, B.F. and G.A. Desborough (1969) Ore microscopy andchemical composition of some laurites. Amer. Mineral., 54, 1330–1346. (3) Bowles, J.F.W., D.
Atkin, J.L.M. Lambert, T. Deans, and R. Phillips (1983) The chemistry, reflectance, and cell sizeof the erlichmanite (OsS2 ) – laurite (RuS2 ) series. Mineral. Mag., 47, 465–471. (4) Lutz, H.D., B.
Müller, T. Schmidt, and T. Stingl (1990) Structure refinement of pyrite-type ruthenium disulfide,
RuS2 , and ruthenium diselenide, RuSe2 . Acta Cryst., C46, 2003–2005. (5) Criddle, A.J. and C.J.
Stanley, Eds. (1993) Quantitative data file for ore minerals, 3rd ed. Chapman & Hall, London,
315.
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35.4

38.82