Greyish fibers of the rare mineral carlosturanite from Auriol Mine, Sampeyre, Cuneo Province, Piedmont, Italy. — Photo: David Hospital · CC BY-SA 4.0
Carlosturanite
Carlosturanite is an IMA-recognized mineral species in the silicate class, with the chemical formula (Mg,Fe²⁺,Ti)₂₁(Si,Al)₁₂O₂₈(OH)₃₄·H₂O.
It crystallizes in the monoclinic crystal system (space group Cm).
Key properties: specific gravity 2.63; Whitish streak; Vitreous, pearly luster; optically biaxial.
IMA symbol Csr, IMA status: approved, named in 1984.
Found in a network of veins crosscutting a metamorphic antigorite serpentinite, in an ophiolite.
It is found associated with Diopside, chrysotile, brucite, magnetite, clinohumite, perovskite, uvarovite (near Sampeyre, Italy).
The name refers to Professor Carlo Sturani (1938–1976), University of Torino, Torino, Italy.