mineral

Polished orbicular jasper (likely ocean jasper)

Silicified microcrystalline quartz/chalcedony with iron-oxide-rich orbicules; commonly called Ocean Jasper

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; tan, ochre, reddish-brown, gray, and bluish colors with circular orbicules, opaque chalcedony, and a dull to waxy polished luster. No obvious cleavage; conchoidal fracture; specific gravity roughly 2.55–2.70.

Identified August 12, 2026More mineral →

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At a glance

Common name: Polished orbicular jasper (likely ocean jasper)
Scientific name: Silicified microcrystalline quartz/chalcedony with iron-oxide-rich orbicules; commonly called Ocean Jasper
Category: mineral
Identified: August 12, 2026
Method: Standard

AI Estimated Value

About $10–$40 for a hand specimen; $30–$150 for attractive polished slabs or cabochons, with exceptional pieces higher.

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 replace volcanic rock and cement radiolarian or spherulitic textures, with iron and manganese producing the colors. Classic Ocean Jasper formed in Oligocene–Miocene volcanic rocks of coastal Madagascar, roughly 5–30 million years old.

Uses & applications

Used for cabochons, ornamental slabs, carvings, display specimens, and lapidary art; generally unsuitable as a major construction stone.

Geological facts

The distinctive circles may be orbicules, former gas cavities, or replaced mineral textures rather than fossils. “Ocean Jasper” is a commercial lapidary name, not a single formally defined mineral species.

Field identification & locations

Identify it by its hard silica-rich body, colorful orbicular patterns, and ability to scratch glass; it should not fizz in dilute acid. Common sources include Madagascar, Mexico, Australia, and Indonesia.