metamorphic
Unakite (Epidotized Granite)
Epidotized Granite (mixture of Orthoclase, Epidote, and Quartz)
Hardness: 6-7 (Mohs scale); Color: Mottled green, pink, and grey; Luster: Dull to vitreous; Crystal Structure: Monoclinic/Triclinic (aggregate); Cleavage: Uneven/Irregular; Specific Gravity: 2.85-3.20
- Hardness
- 6-7 (Mohs scale)
- Color
- Mottled green, pink, and grey
- Luster
- Dull to vitreous
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (Mohs scale); Color: Mottled green, pink, and grey; Luster: Dull to vitreous; Crystal Structure: Monoclinic/Triclinic (aggregate); Cleavage: Uneven/Irregular; Specific Gravity: 2.85-3.20
Formation & geological history
Formed through hydrothermal metasomatism where plagioclase feldspar in granite is replaced by epidote. Usually associated with Proterozoic orographic belts (approx. 1 billion years old).
Uses & applications
Commonly used as a decorative stone, for cabochons in jewelry, carvings, and occasionally as architectural facing or floor tiles due to its durability and unique aesthetics.
Geological facts
First discovered in the Unaka Range of the Appalachian Mountains in the United States, which is how it earned its common name. It is often found as river pebbles that have been smoothed by water action.
Field identification & locations
Identify by its distinctive 'pistachio green' epidote mixed with 'salmon pink' orthoclase feldspar. Commonly found in the Blue Ridge Mountains (USA), South Africa, Sierra Leone, and Brazil. Collectors should look for balanced color distribution.
More like this
