
igneous
Rounded greenish river pebble
Likely altered basalt or greenstone (metabasalt); exact identification requires testing
AI-generated identification · may be incorrectFine-grained, dull to slightly waxy luster, gray-green and brown coloration, smoothly water-worn; likely Mohs 5–6, with no visible cleavage and interlocking microscopic crystals. Composition may include plagioclase, pyroxene, chlorite, epidote, and iron oxides.
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Physical properties
Fine-grained, dull to slightly waxy luster, gray-green and brown coloration, smoothly water-worn; likely Mohs 5–6, with no visible cleavage and interlocking microscopic crystals. Composition may include plagioclase, pyroxene, chlorite, epidote, and iron oxides.
Formation & geological history
Probably basaltic volcanic rock later altered by low-grade metamorphism and rounded by stream or beach transport. Basaltic protoliths commonly formed from oceanic or continental lava, generally from ancient to geologically recent ages.
Uses & applications
Suitable mainly as a landscaping, craft, or decorative stone; not typically valuable for jewelry or construction because the specimen is small and nondescript.
Geological facts
Green coloration commonly reflects chlorite or epidote alteration rather than a single green mineral. A streak, hardness, magnetism, and fresh-break examination would improve identification.
Field identification & locations
Common in riverbeds, beaches, glacial deposits, and areas containing basalt or metamorphosed oceanic crust; identify by its dense, fine texture, rounded shape, and green-gray color. Estimated value: $1–$10 as a common specimen.