부스타마이트

Bustamite is a calcium manganese inosilicate (chain silicate) and a member of the wollastonite group. Magnesium, zinc and iron are common impurities substituting for manganese. Bustamite is the high-temperature polymorph of CaMnSi2O6 and johannsenite is the low temperature polymorph. The inversion takes place at , but may be very slow.Bustamite could be confused with light-colored rhodonite or pyroxmangite, but both these minerals are biaxial (+) whereas bustamite is biaxial (−).

Key facts

Mineral.name: Bustamite
Mineral.category: Inosilicate
Mineral.image: Bustamite.jpg
Mineral.caption: Bustamite (pink) with galena (grey) from Broken Hill, New South Wales, Australia. Specimen size 3.7 cm.
Mineral.formula: CaMn2+Si2O6
Mineral.IMAsymbol: Bst
Mineral.strunz: 9.DG.05 (10 ed) 8/F.18.40 (8 ed)
Mineral.dana: 65.2.1.2
Mineral.system: Triclinic
Mineral.class: Pinacoidal (same H-M symbol)
Mineral.symmetry: I
Mineral.color: Light pink to brownish red Pink color fades on exposure to sunlight
Mineral.habit: Usually tabular or equant to prismatic; commonly massive, often compact and fibrous
Mineral.twinning: Rare. Simple twins with (110) as the composition plane
Mineral.cleavage: {100} perfect; {110} and {10} good; {010} poor
Mineral.mohs: 5.5 to 6.5
Mineral.luster: Vitreous
Mineral.refractive: nα = 1.640 – 1.695, nβ = 1.651 – 1.708, nγ = 1.653 – 1.710