igneous
Rounded quartz-rich pebble, possibly granite or gneiss
Indeterminate granitoid; likely quartz–feldspar–biotite aggregate
AI-generated identification · may be incorrectTan-pink, rounded and weathered, with diffuse dark mineral patches and a dull to slightly vitreous surface. Likely Mohs hardness 6–7; non-cleaving overall, though feldspar grains may show cleavage; specific gravity approximately 2.6–2.7.
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Physical properties
Tan-pink, rounded and weathered, with diffuse dark mineral patches and a dull to slightly vitreous surface. Likely Mohs hardness 6–7; non-cleaving overall, though feldspar grains may show cleavage; specific gravity approximately 2.6–2.7.
Formation & geological history
Probably glacially transported and water-rounded bedrock from the Lake Superior region, commonly Precambrian in age (roughly 1.8–2.7 billion years old). The image is insufficient to distinguish granite from gneiss or a weathered felsic volcanic rock confidently.
Uses & applications
Common material for landscaping, aggregate, and educational collections; this small pebble has little commercial or jewelry value.
Geological facts
The reported location near 46.7°N, 92.0°W is geologically compatible with abundant glacially transported Precambrian granitoid and metamorphic pebbles. Dark areas may be biotite or amphibole rather than fossil material.
Field identification & locations
Look for visible interlocking quartz (gray/glassy), pink or cream feldspar, and black biotite; a streak test should be white, and it should not fizz with dilute acid. A fresh broken surface or hand lens would improve identification.
