metamorphic
Greenstone Pebble
Metabasalt / Greenschist
AI-generated identification · may be incorrectHardness: 5-6 on the Mohs scale, Color: Dull grayish-green, Luster: Dull to sub-vitreous, Crystal structure: Microcrystalline, Cleavage: Poor, Specific Gravity: 2.7-3.0
Identified More metamorphic →
Explore Greenstone Pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5-6 on the Mohs scale, Color: Dull grayish-green, Luster: Dull to sub-vitreous, Crystal structure: Microcrystalline, Cleavage: Poor, Specific Gravity: 2.7-3.0
Formation & geological history
Formed through low-grade regional metamorphism of mafic igneous rocks such as basalt, gabbro, or diabase, typically occurring in ancient orogenic belts and subduction zones.
Uses & applications
Used primarily as decorative aggregate, in landscaping, and occasionally as lapidary material for cabochons and tumbled stones.
Geological facts
The characteristic green color is due to the presence of secondary minerals such as chlorite, epidote, and actinolite that replace the original pyroxenes and plagioclase during metamorphism.
Field identification & locations
Commonly found in stream beds, beaches, and glacial drift in areas with ancient volcanic or metamorphic basements. Identify by its characteristic muted green color and fine-grained texture.
More like this
