metamorphic
Greenschist
Greenschist (Major minerals include Chlorite, Actinolite, and Epidote)
Hardness: 3.5-4.5 (Mohs scale); Color: Dull green to dark forest green with white quartz or calcite veining; Luster: Pearly to vitreous; Crystal structure: Foliated/Schistose; Cleavage: Good in one direction; Specific gravity: 2.8-3.0
- Hardness
- 3
- Luster
- Pearly to vitreous
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 3.5-4.5 (Mohs scale); Color: Dull green to dark forest green with white quartz or calcite veining; Luster: Pearly to vitreous; Crystal structure: Foliated/Schistose; Cleavage: Good in one direction; Specific gravity: 2.8-3.0
Formation & geological history
Formed through low-grade regional metamorphism of mafic igneous rocks (like basalt) under low temperatures and moderate pressures (Greenschist facies). Common in Paleozoic and Mesozoic complexes.
Uses & applications
Used primarily as decorative stone, crushed stone for construction, and sometimes for historical carvings or jewelry if high-grade chlorite is present.
Geological facts
The green color comes from minerals like chlorite and actinolite which form during the metamorphic process. It is a key indicator for geologists that a region has undergone low-grade pressure and heat changes.
Field identification & locations
Identify by its distinctive green hue and foliated (layered) texture often intersected by white veins. Found in mountain belts like the Appalachians, Alps, and coastal cordilleras. Collectors look for pieces with high quartz contrast.
More like this
