mineral

Polished orbicular jasper (likely ocean jasper)

Jasper, a microcrystalline quartz variety; mainly SiO₂ with iron-oxide and other mineral inclusions

AI-generated identification · may be incorrect

Opaque, black-gray, mustard-yellow, and rusty-orange orbicular pattern with a glassy polish; Mohs hardness about 6.5–7, no visible cleavage, cryptocrystalline quartz structure, and specific gravity around 2.6. The rounded specimen is human-polished.

Identified September 15, 2026More mineral →

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At a glance

Common name: Polished orbicular jasper (likely ocean jasper)
Scientific name: Jasper, a microcrystalline quartz variety; mainly SiO₂ with iron-oxide and other mineral inclusions
Category: mineral
Identified: September 15, 2026
Method: Standard

AI Estimated Value

About $10–$40 for a palm-sized polished piece; $50–$150+ for exceptional pattern, color, provenance, or workmanship.

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 fluids cement volcanic ash or replace volcanic rock, with iron oxides producing yellow-orange coloration and orbicular textures. Classic ocean jasper formed in Oligocene–Miocene volcanic rocks of Madagascar, though similar jasper occurs worldwide.

Uses & applications

Used for cabochons, carvings, palm stones, beads, and decorative objects; attractive polished pieces are valued by collectors rather than for industrial use.

Geological facts

“Ocean jasper” is a trade name, not a single formally defined mineral species. Orbicular patterns may consist of radiating quartz, feldspar, chalcedony, and iron-oxide-rich zones.

Field identification & locations

Identify by its opaque hardness, waxy-to-glassy luster, multicolored concentric or orb-like patches, and resistance to scratching by steel; it should not fizz in dilute acid. Common sources include Madagascar, Mexico, Oregon, and Australia.