mineral

Tumbled ocean jasper / orbicular jasper

Jasper, microcrystalline quartz (SiO₂), with iron-oxide and other silicate inclusions

AI-generated identification · may be incorrect

Opaque, polished dark green-brown stone with mottled earthy patterns and possible small orbicular textures; Mohs hardness about 6.5–7, vitreous to waxy luster, no visible cleavage, and quartz-like conchoidal fracture.

Identified September 3, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids cement volcanic ash or replace volcanic rock, with iron and other minerals creating the coloration; many ocean jaspers formed in Paleoproterozoic volcanic environments, notably Madagascar, though exact locality requires testing.

Uses & applications

Used for cabochons, beads, carvings, tumbled stones, and ornamental objects; attractive patterning determines jewelry and collector value.

Geological facts

Jasper is a variety of chalcedony or microcrystalline quartz rather than a single mineral species. Orbicular patterns may resemble small eyes or rosettes but are not necessarily true concentric orbs.

Field identification & locations

Identify by its opaque, fine-grained texture, lack of cleavage, high polish, and resistance to scratching; glass or steel should not easily scratch it. Common sources include Madagascar, India, Brazil, and the western United States.