Extremely rare. Panasqueraite occurs at only two locations, and these are in the same district. This crystalline, massive panasqueiraite is classic for its habit and tannish-flesh color. The luster is actually very good, and I am told this would be a very rich specimen. The remaining parts of the piece is gray quartz, bladed but incomplete ferberite, and muscovite crystals. Ex. Art Soregaroli Collection. From: Panasqueira Mines, Covilhã, Castelo Branco, Portugal. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Panasqueiraite
Panasqueiraite is an IMA-recognized mineral species in the phosphate class, with the chemical formula CaMg(PO₄)(OH).
It crystallizes in the monoclinic crystal system. It is a member of the Titanite structural group.
Key properties: Mohs hardness 5; specific gravity 3.22; White streak; Vitreous luster; optically biaxial.
IMA symbol Psq, IMA status: approved, named in 1978.
A rare mineral found in vein selvages in a hydrothermal Sn–W deposit.
It is found associated with Fluorapatite, wolfeite, topaz, muscovite, sphalerite, quartz, chalcopyrite, pyrrhotite, siderite, arsenopyrite, chlorite, vivianite, althausite, thadeuite.
The name refers to Panasqueira, Portugal, the type locality.