igneous
Water-worn pebble, likely fine-grained volcanic rock
Unidentified mafic volcanic rock; possibly andesite or basalt
AI-generated identification · may be incorrectSmooth, rounded, brown-tan pebble with a dull to slightly waxy surface and no visible crystals. Hardness and specific gravity cannot be determined from the image; the small bright spots may be reflections or mineral grains.
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Physical properties
Smooth, rounded, brown-tan pebble with a dull to slightly waxy surface and no visible crystals. Hardness and specific gravity cannot be determined from the image; the small bright spots may be reflections or mineral grains.
Formation & geological history
Its rounded shape suggests prolonged abrasion in a stream or along a beach. The image does not show enough texture to determine its exact rock type or geological age.
Uses & applications
Primarily a natural collectible or landscaping pebble; no specific industrial or jewelry use can be identified from appearance alone.
Geological facts
Pebble roundness records transport and abrasion, but color alone is not diagnostic: iron staining can make many rock types brown.
Field identification & locations
A volcanic pebble is plausible in the Pacific Northwest, but the specimen cannot be confidently classified from this view. A fresh broken surface, hardness test, and close-up in neutral light would help distinguish basalt/andesite from other common local rocks.
