Roquesite is a member of the chalcopyrite group and has been named after Marice Roques, Professor of Geology.
Chemical Formula – CuInS2
Properties of Roquesite
The following are the key properties of Roquesite
- Cell Data
- Space Group: I42D
- a = 5.51
- c = 11.05
- Z = 4
- Crystal Data
- Point Group: 42m
- Typically as inclusions in other sulphides to 0.3 mm
- X-ray powder pattern: 3.19 (vvs), 1.95 (vs), 1.66 (s), 2.76 (mw), 1.268 (vw), 1.127 (vvw), 3.08 (f)
- Chemical Composition
- Optical Properties
- R1–R2: (400) 25.8–25.0, (420) 25.3–24.8, (440) 24.5–24.5, (460) 23.8–23.9, (480) 23.2–23.4, (500) 22.7–22.9, (520) 22.3–22.6, (540) 22.1–22.4, (560) 21.9–22.3, (580) 21.8–22.2, (600) 21.8–22.2, (620) 21.8–22.2, (640) 21.7–22.2, (660) 21.8–22.2, (680) 21.9–22.3, (700) 22.1–22.5
- Estimated Properties
||Bulk density (electron density)= 4.35 g/cm3
note: Specific gravity of roquesite= 4.8 g/cm3
||PERoquesite = 149.04 barns/electron
U=PERoquesite x ρElectron Density= 649.03 barns/cc.
||Fermion Index = 0.0019834803
Boson Index = 0.9980165197
||Roquesite is not radioactive
How to Identify Roquesite
Roquesite is opaque and in a polished section is gray with a slight bluish tint. It has a metallic luster and very weak anisotropism.
Roquesite is distributed in the following places:
- In France, from Charrier, Allier [TL]; in Lautaret Pass, Hautes-Alpes; at La Telhaie, Morbihan; and from Vaultry, Haute-Vienne.
- In the Geevor mine, St. Just, Cornwall, England. At Listulli, Telemark, and Langban, Varmland, Sweden.
- From the Radka deposit, Pazardzhik, Bulgaria.
- In Canada, from Mount Pleasant, New Brunswick.
- At the Sure Fire mine, Pyramid district, Washoe Co., Nevada, USA.
- Found in the Mangabeira tin deposit, Goias, Brazil.
- At Cinovec (Zinnwald), Czech Republic From Syrymbet, Kazakhstan.
- In the Akenobe and Ikuno mines, Hyogo Prefecture, Japan.
- In the Ulsan mine, Kyongsang Province,South Korea.
- At the Tosham tin prospect, Bhiwani district, Haryana, India.
Occurrence of Roquesite and Useful Mineral Association
Roquesite occurs in association with copper sulfides at high-temperature Sn–W–Bi–Mo hydrothermal veins in highly metamorphosed rocks (Charrier, France); a late-stage mineral in a skarn Fe–W ore pipe (Ulsan mine, South Korea); in magnetite-bearing massive chalcopyrite ore (Akenobe mine, Japan).
Mineral associations include Chalcopyrite, bornite, cubanite, covellite, sphalerite, tetrahedrite, emplectite, wittichenite, stannoidite, pyrite, l¨ollingite, arsenopyrite, bismuth, cassiterite, ferberite, and magnetite.