Unakite
Image: User:JohnArmagh (Public domain)
Mineral NameUnakite
Chemical FormulaRock (composed of Epidote, Orthoclase, Quartz)
Mohs Hardness6.5
Crystal Systemcubic
Lustervitreous
Streak ColorWhite
CleavagePoor to absent (due to mixed mineral components)
FractureUneven to conchoidal
Specific Gravity2.8
Colorsgreen, pink, red, grey, white
TransparencyTranslucent to opaque
Type LocalityUnaka Mountains, North Carolina, USA
Mineral GroupRock (altered granite); constituent minerals are silicates
Usesjewelry, ornamental stone, carving
Associated Mineralsepidote, orthoclase, quartz
Raritycommon
Description
A distinctive metamorphic rock characterized by its mottled appearance of pistachio green epidote, pink to red orthoclase feldspar, and often colorless to grey quartz. The image displays both rough and polished (cabochon) forms.
Geological Context
Unakite is an altered granite, formed when granitic rocks undergo metamorphism, leading to the albitization of plagioclase feldspar into epidote. It is typically found in regional metamorphic terrains.
