metamorphic

Polished orbicular jasper (likely ocean jasper)

Siliceous microcrystalline quartz/chalcedony aggregate; commonly sold as Ocean Jasper

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; reddish-brown, green, and yellow concentric orbicular pattern; dull to waxy unpolished luster and vitreous polish; no obvious cleavage; specific gravity about 2.55–2.70. The visible circles are mineral-rich spherulitic or orbicular structures.

Identified September 11, 2026More metamorphic →

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Physical properties

Formation & geological history

Formed by silica-rich volcanic or hydrothermal processes that produced chalcedony, quartz, and iron-bearing minerals; the exact locality and geological age cannot be confirmed from the image. Ocean Jasper is famously associated with Miocene volcanic rocks near Madagascar.

Uses & applications

Used for cabochons, beads, carvings, polished palm stones, and decorative objects; it has little industrial value compared with ordinary quartz-rich rock.

Geological facts

Its orbicular pattern is natural, not painted, and varies greatly between pieces. Similar orbicular jaspers occur worldwide, so “Ocean Jasper” should be used only when locality is documented.

Field identification & locations

Identify by testing for glass-scratching hardness, dense silica-like weight, waxy texture, and natural concentric orbs; avoid confusing it with dyed or resin-coated material. Common sources include Madagascar, Mexico, Australia, and Indonesia.