Rock Identifier
Polished orbicular jasper (likely ocean jasper) (Microcrystalline quartz (SiO₂) with iron oxides and accessory minerals) — mineral
mineral

Polished orbicular jasper (likely ocean jasper)

Microcrystalline quartz (SiO₂) with iron oxides and accessory minerals

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; orange, cream, black, and green mottling; opaque, waxy to vitreous luster; cryptocrystalline quartz with no visible cleavage. The rounded shape indicates tumbling or natural water wear.

Identified More mineral
Explore Polished orbicular jasper (likely ocean jasper) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Hardness about 6.5–7 Mohs; orange, cream, black, and green mottling; opaque, waxy to vitreous luster; cryptocrystalline quartz with no visible cleavage. The rounded shape indicates tumbling or natural water wear.

Formation & geological history

Formed when silica-rich fluids silicified volcanic rock, with iron-oxide staining and contrasting mineral inclusions; Madagascar ocean jasper formed in Oligocene–Miocene volcanic environments. Exact locality cannot be confirmed from the image.

Uses & applications

Used for cabochons, beads, carvings, and polished collectibles; too variable and generally soft for high-value fine jewelry. Occasionally used decoratively as ornamental stone.

Geological facts

The black and orange patterning commonly comes from manganese or iron oxides and darker silicate minerals. “Ocean jasper” is a trade name generally associated with orbicular jasper from Madagascar.

Field identification & locations

Identify by its opaque body, multicolor orbicular or brecciated pattern, waxy polish, and inability to scratch with a steel knife; quartz should scratch glass. Common jasper sources include Madagascar, Oregon, India, Brazil, and Australia.