metamorphic

Weathered greenstone / altered rock fragment

Probable chlorite–epidote–actinolite-rich metavolcanic rock; exact identification requires testing

AI-generated identification · may be incorrect

Pale green to gray-green, dull to slightly waxy luster, fine-grained and irregularly fractured; likely Mohs 5–6, with no obvious cleavage or visible crystals. The apparent banding and green coloration suggest alteration rather than a single gem mineral.

Identified September 13, 2026More metamorphic →

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Physical properties

Formation & geological history

Likely formed when basaltic volcanic rock underwent low- to medium-grade metamorphism and hydrothermal alteration, commonly during ancient tectonic events; age cannot be determined visually. Typical settings include metamorphic belts and altered oceanic crust.

Uses & applications

Primarily a geological or lapidary specimen; comparable greenstones may be polished for decorative objects, beads, and cabochons, but this fragment has little commercial use without confirmation of quality.

Geological facts

“Greenstone” is a broad field term covering several rocks, including chlorite schist, greenschist, serpentinite, and altered basalt. Green color alone is not diagnostic.

Field identification & locations

Look for a green fine-grained matrix, possible foliation, and moderate hardness; a streak, density, acid, and thin-section examination would help distinguish it from serpentine, jade, or slag. Common in metamorphic terrains worldwide.