[ Top ] [ Japanese ]

Wollastonite (Photo) [abbr. Wo ]

Year of discovery: 1818 (World), 1891 (Japan)

Locality list: 358 localities of wollastonite

• CaSiO₃
• [Ca²⁺₃][Si₃O₉]^6-

• Class: Wollastonite group < 3-periodic < Pyroxenoid
• Class: Inosilicate (Single chain)
• Soluble in: HCl (Decompose)
• Magnetism: Diamagnetic
• Fluorescence: UV excitation (Bluish green-Yellow)

• Polymorph: Pseudowollastonite (Artificial, High temperature)

• Ca => Mn: Vittinkiite, Pyroxmangite
• Ca => Fe: Pyroxferroite
• Ca => Mg: Akimotoite

• Ca₂ => CaNaH: Pectolite
• Ca₂ => CaFe: Ferrobustamite
• Ca₂ => CaMn: Bustamite
• Ca₂ => ScH: Cascandite

• Color: White, Pale gray, Pale brown
• Streak: White
• Luster: Vitreous
• Diaphaneity: Transparent-Translucent

• Habit: Fibrous, Tabular

• Cleavage: Perfect on {100} (1 planes), Good on {001} and {102} (2 planes)
• Hardness: 4.5-5
• Density: 3.0

• System: Triclinic (1A, 3A, 4A, 5A, 7A), Monoclinic (2M, Parawollastonite) (Layer-stacking polytype)
• Group: (-1), P(-1)
• Lattice: a=7.9, b=7.3, c=7.1, α=90.1, β=95.2, γ=103.4

Etymology: William Hyde Wollaston (1766-1828), British mineralogist