Capranicaite
Capranicaite is an IMA-recognized mineral species in the silicate class, with the chemical formula KCaNaAl₄B₄Si₂O₁₈.
It crystallizes in the monoclinic crystal system (space group P2_1/n).
Key properties: Mohs hardness 6; specific gravity 2.41; White streak; Vitreous luster; optically biaxial.
IMA symbol Cpc, IMA status: approved, named in 2009.
A late-stage metasomatic product inside miarolitic cavities in a block of feldspathoid- bearing syenite in an ignimbrite unit ejected from a complex volcano.
It is found associated with K-feldspars, plagioclase, andradite, hornblende, biotite, magnetite, a member of the sodalite-haüyne series, titanite, apatite, zircon, a B-Be-Si phase.
The name refers to the locality from which the first specimens were obtained.