sedimentary

Polished orbicular jasper

Siliceous microcrystalline quartz/chalcedony (SiO₂), commonly with iron-oxide and volcanic inclusions

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; tan, cream, gray, and brown concentric or brecciated patterns; waxy to dull luster; cryptocrystalline, with no visible cleavage and conchoidal fracture. The smooth surface indicates natural or human polishing.

Identified September 16, 2026More sedimentary →

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At a glance

Common name: Polished orbicular jasper
Scientific name: Siliceous microcrystalline quartz/chalcedony (SiO₂), commonly with iron-oxide and volcanic inclusions
Category: sedimentary
Identified: September 16, 2026
Method: Standard

AI Estimated Value

Approximately $5–$30 for a small ordinary polished piece; $30–$100+ for unusually vivid patterning, size, or confirmed locality.

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

Formed when silica-rich fluids replaced or cemented volcanic sediment and filled cavities, preserving orbicular or flow-like patterns; typically Cenozoic to older volcanic-terrain material. Exact age and locality cannot be determined from the photograph.

Uses & applications

Used for cabochons, carvings, beads, polished specimens, and decorative stone; too small for construction use.

Geological facts

Jasper is an opaque variety of chalcedony, and its colors commonly come from hematite, limonite, or other iron minerals. Patterned varieties are often sold under locality-based trade names.

Field identification & locations

Identify it by its opaque silica body, fine grain, hardness, and distinctive rounded or layered markings; it should scratch glass but not be scratched by a steel knife. Common sources include Oregon, Idaho, Madagascar, Mexico, and Australia.