Ocean Jasper Identification Guide

What Ocean Jasper Looks Like

Ocean Jasper is a trade name for an orbicular variety of silica (jasper/chalcedony with spherulitic structures) from Madagascar, famous for its circular "eye" or orb patterns set in a colorful matrix. Specimens combine green, white, cream, pink, yellow, red, and gray, with concentric rings, polka-dot orbs, and small drusy quartz-lined vugs. It is opaque to faintly translucent and polishes to a glassy shine.

• Color: multicolored — greens, whites, pinks, yellows, reds, grays
• Luster: vitreous to waxy when polished; sparkly in drusy pockets
• Transparency: opaque, occasionally translucent in chalcedony zones
• Pattern: spherical orbs/eyes, concentric rings, mottling, drusy cavities

Step-by-Step Field ID Checklist

1. Look for orbs: the defining feature is rounded, eye-like spherulites scattered through the stone.
2. Check for druzy pockets: tiny sparkling quartz crystal cavities are common and characteristic.
3. Note the multicolor palette: mixed greens, pinks, whites, and yellows in one piece.
4. Test hardness: scratches glass, resists a knife (Mohs ~6.5–7).
5. Examine the break: conchoidal, no cleavage.
6. Confirm opacity: mostly opaque with a smooth glassy polish.

Key Diagnostic Tests

• Hardness: ~6.5–7 (chalcedony/quartz); scratches glass.
• Streak: white.
• Acid: no fizz (silica), separating it from carbonate orbicular rocks.
• Cleavage/fracture: none; conchoidal/splintery.
• Density: ~2.6 g/cm³.

Common Look-Alikes and How to Tell Them Apart

• Other orbicular jaspers (e.g., "poppy" jasper, leopard skin jasper): these also show orbs; genuine Ocean Jasper specifically comes from coastal Madagascar deposits and typically shows the combination of multicolor orbs plus small drusy quartz vugs and pastel greens/pinks. Drusy cavities and the pastel palette favor Ocean Jasper.
• Ocean Jasper imitations / dyed jasper: uniform unnatural colors or dye concentrated in cracks; verify Mohs ~7 and natural drusy pockets.
• Agate: translucent and concentrically banded throughout; Ocean Jasper is opaque with discrete orbs in matrix.
• Orbicular granite/rhyolite: igneous, with feldspar/quartz mineralogy and duller appearance; not silica-replacement jasper and usually larger orbs.
• Malachite/carbonate orbicular stones: softer and fizz (carbonates) or much greener banded — Ocean Jasper is hard and acid-inert.

Where Ocean Jasper Is Found

Ocean Jasper comes from the northwest coast of Madagascar (notably the Marovato area near Ambolobozo Peninsula), where it occurs in silicified volcanic rock often exposed at the shoreline and worked at low tide — hence the name. The original mine was famously depleted, and later deposits along the same coast supply newer material. It is sold as polished slabs, spheres, cabochons, and tumbled stones. As a silica-replacement/spherulitic rock, its orbs reflect radial crystal growth during silicification.