Dark green crystals of phosphovanadylite-Ca with light green sincosite. Phosphovanadylite-(Ca) is a relatively new mineral (IMA 2011-101) known from only one locality worldwide: South Rasmussen Mine, Soda Springs, Caribou County, Idaho, United States of America. — Photo: David Hospital · CC BY-SA 4.0
Phosphovanadylite-Ca
Phosphovanadylite-Ca is an IMA-recognized mineral species in the phosphate class, with the chemical formula Ca[V⁴⁺₄P₂O₁₂(OH)₄]·12H₂O.
It crystallizes in the cubic crystal system (space group I-43m). It is a member of the Phosphovanadylite structural group.
Key properties: Mohs hardness 2; specific gravity 2.02; Very pale greenish blue streak; Vitreous luster.
IMA symbol Pvd-Ca, IMA status: approved, named in 2011.
Crystallized at ambient temperatures from late-stage aqueous solutions of near neutral pH under relatively reducing conditions in phosphatic black mudstone.
It is found associated with Quartz, fluorapatite, hydroxylapatite, pyrite, sphalerite, sincosite, native Se.
As the Ca analog of phosphovanadylite, which is now renamed as phosphovanadylite-Ba.