mineral
Tumbled brown stone, possibly chert or iron-stained quartzite
Indeterminate from photograph; possible microcrystalline quartz (SiO₂)
AI-generated identification · may be incorrectSmooth, rounded, opaque brown specimen with a dull to weakly waxy luster; likely hardness about 6.5–7 Mohs if chert or quartzite. No visible crystals, cleavage, or layering; specific gravity may be approximately 2.6–2.7.
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Physical properties
Smooth, rounded, opaque brown specimen with a dull to weakly waxy luster; likely hardness about 6.5–7 Mohs if chert or quartzite. No visible crystals, cleavage, or layering; specific gravity may be approximately 2.6–2.7.
Formation & geological history
Could be naturally rounded or mechanically tumbled from silica-rich rock, with brown coloration caused by iron oxides. The formation age and locality cannot be determined visually.
Uses & applications
Commonly used as a decorative tumbled stone, craft material, or lapidary specimen; not identifiable as a gem-quality material from this image.
Geological facts
Chert and quartzite resist weathering and commonly produce smooth pebbles; iron staining can range from yellow-brown to reddish brown.
Field identification & locations
Test hardness against glass: scratching glass supports quartz-rich material, while a steel nail should not scratch it. A streak, specific-gravity, and close examination for grain texture are needed to distinguish chert, quartzite, jasper, or another brown stone.
