metamorphic
Greenschist / Greenstone
Greenschist (composed of chlorite, epidote, actinolite, albite)
Hardness: 3.5-6 on Mohs scale; Color: Dark olive green to dull grayish-green; Luster: Dull to silky or sub-vitreous when wet; Structure: Foliated to fine-grained massive; Cleavage: Poor to moderate schistosity
- Hardness
- 3
- Color
- Dark olive green to dull grayish-green
- Luster
- Dull to silky or sub-vitreous when wet
Identified More metamorphic →
Explore Greenschist / Greenstone in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 3.5-6 on Mohs scale; Color: Dark olive green to dull grayish-green; Luster: Dull to silky or sub-vitreous when wet; Structure: Foliated to fine-grained massive; Cleavage: Poor to moderate schistosity
Formation & geological history
Formed through low-grade regional metamorphism of mafic igneous rocks (such as basalt or gabbro) under low temperatures and moderate pressures (greenschist facies). Common in accretionary wedges along subduction zones.
Uses & applications
Historically used for making stone axes, carvings, and decorative stones. Used as construction aggregate, ballast, and landscaping stone today.
Geological facts
Greenschist gets its characteristic greenish color from green minerals like chlorite, epidote, and actinolite. It is often found along coastal beaches near tectonic plate boundaries, such as the Pacific Ring of Fire.
Field identification & locations
Identified by its distinctive greenish color, soft-to-medium hardness, fine-grained texture, and wet smooth luster. Highly common along ocean beaches, riverbeds, and mountainous metamorphic terrains.
More like this
