The brown yakhontovite PS is ~ 1½ mm in diameter. Yakhantovite PS after tennantite with clinoatacamite and small spheres of conichalcite. The back of the specimen has clinotyrolite. (There are larger and more complete yakhontovite PS on the specimen but I liked the contrast with clinoatacamite.) From: La Amorosa mine, San Rafael claim, Villahermosa del Rio, Castellón, Valencian Community, Spain — Photo: Modris Baum · CC0
Clinoatacamite
Clinoatacamite is an IMA-recognized mineral species in the halide class, with the chemical formula Cu₂Cl(OH)₃.
It crystallizes in the monoclinic crystal system (space group P2_1/n). It is a member of the Atacamite structural group.
Key properties: Mohs hardness 3; specific gravity 3.77; Adamantine to vitreous luster; optically biaxial.
IMA symbol Cata, IMA status: approved, named in 1993.
An oxidation product of other copper minerals.
It is found associated with Atacamite, paratacamite, gypsum, alunite (Chuquicamata, Chile); atacamite, zincian paratacamite, caracolite, schwartzembergite, osarizawaite-beaverite.
As the monoclinic polymorph of atacamite.