igneous
Weathered vesicular volcanic rock (likely pumice or scoria)
Vesicular volcanic glass/rock, commonly rhyolitic pumice or basaltic scoria
AI-generated identification · may be incorrectLight gray, highly porous, and irregularly vesicular with a dull to slightly glassy luster; likely hardness about 5–6, with no obvious cleavage and low density. The pale color favors pumice, though the image alone cannot distinguish it confidently from weathered scoria.
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Physical properties
Light gray, highly porous, and irregularly vesicular with a dull to slightly glassy luster; likely hardness about 5–6, with no obvious cleavage and low density. The pale color favors pumice, though the image alone cannot distinguish it confidently from weathered scoria.
Formation & geological history
Formed when gas-rich lava rapidly cooled, trapping bubbles; likely Cenozoic or younger, depending on locality. Common in volcanic ash deposits, lava flows, beaches, and areas near explosive eruptions.
Uses & applications
Used as lightweight aggregate, abrasive, landscaping stone, soil amendment, and exfoliating material; attractive pieces may be collected, but this specimen has little commercial value.
Geological facts
Vesicles are frozen gas bubbles, and pumice can sometimes float until its pores become water-filled. Weathering has rounded and obscured the original texture.
Field identification & locations
Look for abundant connected pores, very low weight, a frothy texture, and lack of visible mineral grains; pumice is usually pale, while scoria is commonly dark red or black. Common worldwide in volcanic regions, including the western United States, Italy, Iceland, and New Zealand.
