Rock Identifier
Ocean Jasper (Silicon Dioxide (SiO2) with various inclusions) — igneous/sedimentary mixed (Orbicular Jasper)
igneous/sedimentary mixed (Orbicular Jasper)

Ocean Jasper

Silicon Dioxide (SiO2) with various inclusions

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Variegated greens, pinks, creams, and browns; Luster: Vitreous to waxy; Structure: Cryptocrystalline (Trigonal); Cleavage: None; Specific Gravity: 2.6-2.9.

Hardness
6
Color
Variegated greens, pinks, creams, and browns
Luster
Vitreous to waxy
Identified More igneous/sedimentary mixed (orbicular jasper) →
Explore Ocean Jasper in the encyclopedia →

Identify your own rocks.

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

App StoreGoogle Play

Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Variegated greens, pinks, creams, and browns; Luster: Vitreous to waxy; Structure: Cryptocrystalline (Trigonal); Cleavage: None; Specific Gravity: 2.6-2.9.

Formation & geological history

Formed as a result of rhythmic precipitation of silica around a nucleus in volcanic environments. Unique to the coastline of Madagascar, these deposits are found in intertidal zones and are usually andesitic or rhyolitic in host Rock origin.

Uses & applications

Primary use is in the jewelry and lapidary trades for cabochons, beads, and ornamental carvings. It is highly valued by crystal collectors for its aesthetic 'eye' or 'orb' patterns.

Geological facts

Ocean Jasper is only found in Madagascar. The most famous deposit was 'rediscovered' in 1999 along the coast, where it could only be mined at low tide by boat, making it one of the more rare and geographically limited jaspers.

Field identification & locations

Identify in the field by its distinct orbicular (circular) patterns, which look like small bullseyes or flower-like structures embedded in a chalcedony matrix. It is found on the northwest shore of Madagascar.

More like this

Other igneous/sedimentary mixed (orbicular jasper) specimens

Mixed polished river stones (Likely quartz, quartzite, chert/jasper, and possibly limestone or marble) — mineral

Mixed polished river stones

Likely quartz, quartzite, chert/jasper, and possibly limestone or marble

mineral
Leopard Skin Jasper (Silicon Dioxide (SiO2) with mineral inclusions) — sedimentary

Leopard Skin Jasper

Silicon Dioxide (SiO2) with mineral inclusions

sedimentary
Polished orbicular jasper (likely ocean jasper) (Silicified microcrystalline quartz (SiO₂), commonly called orbicular jasper or ocean jasper) — mineral

Polished orbicular jasper (likely ocean jasper)

Silicified microcrystalline quartz (SiO₂), commonly called orbicular jasper or ocean jasper

mineral
Mixed polished gemstone bead bracelet, likely ocean jasper, agate, and quartz varieties (Mostly microcrystalline quartz (SiO₂), with possible chalcedony, jasper, and minor feldspar or other inclusions) — gemstone

Mixed polished gemstone bead bracelet, likely ocean jasper, agate, and quartz varieties

Mostly microcrystalline quartz (SiO₂), with possible chalcedony, jasper, and minor feldspar or other inclusions

gemstone
Mixed river gravel, prominently iron-stained chert/jasper (Microcrystalline quartz (SiO₂), chiefly chert/jasper with iron-oxide staining; mixed clasts may include quartzite and other silicates) — sedimentary

Mixed river gravel, prominently iron-stained chert/jasper

Microcrystalline quartz (SiO₂), chiefly chert/jasper with iron-oxide staining; mixed clasts may include quartzite and other silicates

sedimentary
Orbicular rhyolite (likely) (Silica-rich volcanic rock, chiefly quartz and feldspar with orbicular aggregates of feldspar, quartz, and mafic minerals) — igneous

Orbicular rhyolite (likely)

Silica-rich volcanic rock, chiefly quartz and feldspar with orbicular aggregates of feldspar, quartz, and mafic minerals

igneous