| Alloclasite | |
|---|---|
| General | |
| Category | Mineral |
| Formula (repeating unit) | (Co,Fe)AsS |
| IMA symbol | All |
| Identification | |
| Color | Steel gray to silver |
| Fracture | Irregular/Uneven, Sub-Conchoidal |
| Mohs scale hardness | 5 |
| Luster | Metallic |
| Streak | Nearly black |
| Diaphaneity | Opaque |
| Specific gravity | 5.95 |
Alloclasite, or (Co,Fe)AsS, is a sulfosalt mineral (IMA symbol: Acl).[1] It is a member of the arsenopyrite group. Alloclasite crystallizes in the monoclinic system and typically forms as columnar to radiating acicular prismatic clusters. It is an opaque steel-gray to silver-white, with a metallic luster and a black streak. It is brittle with perfect cleavage, a Mohs hardness of 5 and a specific gravity of 5.91–5.95.[2]
It was first described in 1866 for an occurrence in Romania.[3] Its name is derived from Greek for "other" and "to break," in reference to its distinct cleavage which distinguished it from the similar appearing mineral marcasite.[4][2]
The mineral is monoclinic in the P21 space group.[5]
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.
- ^ a b http://rruff.geo.arizona.edu/doclib/hom/alloclasite.pdf Handbook of Mineralogy
- ^ http://www.mindat.org/min-134.html Mindat data
- ^ http://www.webmineral.com/data/Alloclasite.shtml Webmineral data
- ^ Scott, J.D.; Nowacki, W. (1976). "The crystal structure of alloclasite, CoAsS, and the alloclasite-cobaltite transformation". The Canadian Mineralogist. 14: 561–566.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction