Wollastonite
Image: Modification (size comparison) added by <a href="//commons.wikimedia.org/wiki/User:Chmod007" title="User:Chmod007">David Remahl</a>. (Public domain)
Mineral NameWollastonite
Chemical FormulaCaSiO3
Mohs Hardness4.5
Crystal Systemtriclinic
Lustervitreous
Streak Colorwhite
Cleavageperfect on {100}, good on {001}, distinct on {102}
Fractureuneven
Specific Gravity2.9
Colorswhite, gray, pale green, pale brown
Transparencytranslucent
Type LocalityWillsboro, New York, USA
Mineral Groupsilicates
Usesindustrial filler, ceramics, paints, plastics, flux in metallurgy
Associated Mineralscalcite, diopside, garnet, vesuvianite, epidote
Raritycommon
Description
This image displays a blocky, off-white to light gray specimen of wollastonite, showing a fibrous or bladed habit with visible cleavage planes. A U.S. 1 cent coin provides scale, highlighting the mineral's texture.
Geological Context
Wollastonite commonly forms in contact metamorphic rocks, particularly in metamorphosed impure limestones or dolomites where silica reacts with calcite. It is also found in skarn deposits.
