gemstone

Polished orbicular jasper or rhyolitic jasper

Silica-rich microcrystalline quartz/chalcedony (SiO₂), likely jasper with contrasting mineral veins

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; gray-green to brown, opaque, with a waxy to vitreous polish and irregular pale vein network. Microcrystalline quartz lacks visible cleavage and commonly has specific gravity near 2.6.

Identified September 7, 2026More gemstone →

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At a glance

Common name: Polished orbicular jasper or rhyolitic jasper
Scientific name: Silica-rich microcrystalline quartz/chalcedony (SiO₂), likely jasper with contrasting mineral veins
Category: gemstone
Identified: September 7, 2026
Method: Standard

AI Estimated Value

About $3–$15 for a small common tumbled stone; $20–$60 if unusually patterned, large, or sold as a quality cabochon.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms when silica-rich volcanic or sedimentary material is replaced and cemented by chalcedony/quartz, with later fractures filled by lighter minerals. Exact age cannot be determined from the image; jasper occurs in many Paleozoic–Cenozoic deposits.

Uses & applications

Used for cabochons, beads, worry stones, carvings, and ornamental objects; generally decorative rather than industrial.

Geological facts

The rounded shape and high polish indicate a human-worked tumbled or carved specimen. Similar material is often sold as “brecciated jasper,” “rhyolite jasper,” or occasionally “crocodile jasper,” though visual identification alone is uncertain.

Field identification & locations

Look for opaque fine grain, no glassy translucence, hardness sufficient to scratch ordinary glass, and natural-looking mineral veins or breccia patterns. Common sources include India, Madagascar, Indonesia, Mexico, and the western United States.