Derriksite is a very rare uranium mineral with the chemical formula Cu4(UO2)(SeO3)2(OH)6•H2O. It is a secondary mineral that contains copper, uranium and the rarer selenium. It is a bright green to duller bottle green colour. Its crystal habit is acicular, it is most likely to be found along with the uranyl selenium mineral demesmaekerite, but derriksite is much rarer than demesmaekerite. It is named after Jean Marie Francois Joseph Derriks (1912–1992), geologist and administrator of the Union Minière du Haut Katanga (UMHK). It has a Mohs hardness of about 2.[2]
| Derriksite | |
|---|---|
 | |
| General | |
| Category | Oxide minerals |
| Formula (repeating unit) | Cu4(UO2)(SeO3)2(OH)6•H2O |
| IMA symbol | Drk[1] |
| Strunz classification | 4.JG.30 |
| Crystal system | Orthorhombic |
| Crystal class | Pyramidal (mm2) H-M symbol: (mm2) |
| Space group | Pn21m |
| Identification | |
| Colour | Bottle green, green |
| Cleavage | {???} perfect, {010} good |
| Diaphaneity | Translucent |
| Specific gravity | 4.72 |
| Other characteristics |  Radioactive |
References
edit- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ "Derriksite". mindat.org. Retrieved January 11, 2013.
Further reading
edit- Verbeek, Th.; Pierrot, R. (1971). "La Derriksite Cu4(UO2)(SeO3)2•(H2O) une nouvelle espece minérale" (PDF). Bull. Soc. Fr. Mineral. Cristallogr. 94: 534–537.
- Ginderow, D.; Cesbron, F. (1983). "Structure de la derriksite, Cu4(UO2)(SeO3)2•(H2O)". Acta Crystallographica Section C. 39 (12): 1605. doi:10.1107/S0108270183009439.
- Frost, Ray; Jagannadha Reddy, B.; Dickfos, Marilla (2008). "An application of near infrared and mid-infrared spectroscopy to the study of uranyl selenite minerals: Derriksite, demesmaekerite, guilleminite and haynesite". Journal of Near Infrared Spectroscopy. 16 (5): 455–469. Bibcode:2008JNIS...16..455F. doi:10.1255/jnirs.813. S2CID 96401790.