igneous
Polished red granite or rhyolite pebble
Likely pink/red granite, composed chiefly of quartz, alkali feldspar, and mica; exact identification requires testing
AI-generated identification · may be incorrectFine-to-medium grained, rounded and polished, reddish-brown with pale mineral flecks and subdued vitreous-to-waxy luster. Typical hardness is about 6–7 Mohs; no visible cleavage as a whole rock, and specific gravity roughly 2.6–2.7.
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Physical properties
Fine-to-medium grained, rounded and polished, reddish-brown with pale mineral flecks and subdued vitreous-to-waxy luster. Typical hardness is about 6–7 Mohs; no visible cleavage as a whole rock, and specific gravity roughly 2.6–2.7.
Formation & geological history
Formed when silica-rich magma crystallized slowly underground (granite) or rapidly near the surface (rhyolite), likely hundreds of millions to billions of years old; later weathered and rounded by transport, then polished by humans.
Uses & applications
Used as a decorative pebble, paperweight, landscaping stone, and occasionally in countertops or construction aggregate; this small specimen has minimal jewelry or commercial value.
Geological facts
The red color generally comes from iron-bearing potassium feldspar, while gray or white grains are quartz and feldspar. A glass-scratch test and acid test can help distinguish it from softer red jasper.
Field identification & locations
Common in glacial deposits, river gravels, and crushed-stone products worldwide, especially regions underlain by pink granite. Look for interlocking grains and a speckled texture rather than the uniform appearance of jasper.
