igneous
Tumbled greenish stone, likely altered basalt or serpentinite
Probable basaltic/mafic rock with secondary chlorite, epidote, or serpentine minerals
AI-generated identification · may be incorrectFine-grained, rounded and polished, with olive-green, brown, and rusty mottling; dull to slightly waxy luster and no visible cleavage. Estimated hardness is about 5–6 Mohs, though the porous weathered surface makes identification uncertain.
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Physical properties
Fine-grained, rounded and polished, with olive-green, brown, and rusty mottling; dull to slightly waxy luster and no visible cleavage. Estimated hardness is about 5–6 Mohs, though the porous weathered surface makes identification uncertain.
Formation & geological history
Likely a weathered stream or beach pebble derived from mafic volcanic rock and later hydrothermally altered; basalt commonly formed in the Mesozoic or younger, but its exact age cannot be determined from the image.
Uses & applications
Suitable for landscaping, craft stones, tumbling, and casual collecting; not typically used as a gemstone or high-value ornamental material.
Geological facts
Green coloration may result from chlorite, epidote, or serpentine replacing original basaltic minerals, while orange-brown patches are iron oxides.
Field identification & locations
A hand lens should reveal a fine crystalline texture; a streak, hardness, magnetism, and acid test can help distinguish basalt, serpentinite, and other greenstones. Common in volcanic terrains and glacial or stream gravels.
