metamorphic

Greenstone, likely chlorite-rich schist

Chlorite schist; chiefly chlorite, actinolite/amphibole, feldspar, and quartz

AI-generated identification · may be incorrect

Hardness about 2–6, depending on composition; gray-green to moss-green, with a dull to silky luster and foliated, platy texture. Visible mica-like flakes and weak schistosity are characteristic; cleavage is mainly along the foliation.

Identified August 16, 2026More metamorphic →

Explore Greenstone, likely chlorite-rich schist in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed when mafic volcanic rock such as basalt underwent low- to medium-grade metamorphism, commonly during mountain building. Such rocks are typically Paleozoic to Precambrian, though age cannot be determined from the photo.

Uses & applications

Used locally as decorative stone, aggregate, or landscaping rock; attractive pieces may be sold as greenstone specimens, but it is generally not a gemstone.

Geological facts

The broad term “greenstone” also includes altered basalt, greenschist, and serpentinite, so exact identification requires hardness, streak, magnetism, and thin-section or chemical testing.

Field identification & locations

Common in metamorphic belts worldwide, including the Appalachians, Canadian Shield, New Zealand, and greenstone belts. Look for green color, foliation, flaky cleavage, and a lack of glassy volcanic texture.