mineral
Polished/tumbled jasper, likely brecciated jasper
Jasper: microcrystalline quartz (SiO₂), with iron-oxide and other mineral impurities
AI-generated identification · may be incorrectOpaque reddish-brown, cream, and gray material with rounded polishing and irregular internal bands or brecciation. Quartz hardness is about 6.5–7 Mohs; dull to glassy/waxy luster; no obvious cleavage; specific gravity approximately 2.55–2.70.
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Physical properties
Opaque reddish-brown, cream, and gray material with rounded polishing and irregular internal bands or brecciation. Quartz hardness is about 6.5–7 Mohs; dull to glassy/waxy luster; no obvious cleavage; specific gravity approximately 2.55–2.70.
Formation & geological history
Jasper forms when silica-rich fluids replace or cement sediment and volcanic material, commonly incorporating iron oxides that create red and brown colors. The specimen is human-polished; its exact geological age and source cannot be determined visually.
Uses & applications
Used for cabochons, beads, carvings, bookends, and decorative objects. This small tumbled piece is generally a low-cost lapidary or collector specimen.
Geological facts
The sharp color boundaries and opaque appearance favor jasper over agate, which is typically more translucent and distinctly banded. Iron oxidation commonly produces the red coloration.
Field identification & locations
Likely identifiable by its opacity, fine-grained texture, earthy red-brown color, and lack of visible crystal faces. Jasper is widespread, including in glacial sediments around Michigan, so the reported location is plausible; provenance would require testing or locality information.
