Cobra Jasper Identification Guide

What Cobra Jasper Looks Like

Cobra jasper is a trade name for a patterned variety of jasper — an opaque, microcrystalline quartz (chalcedony) rock colored by iron and clay impurities. It is prized for wavy, banded, snakeskin-like markings in earthy tones of tan, cream, brown, gray, olive, and reddish-brown, often with flowing lines or scale-like patterns reminiscent of a cobra's hide. Luster is dull to waxy on rough surfaces and glassy when polished; it is opaque to faintly translucent on thin edges.

Step-by-Step Field ID Checklist

1. Examine the pattern. Look for flowing, wavy, snakeskin or scale-like bands in earthy browns, tans, and grays.
2. Check opacity. Jasper is opaque; only thin edges may pass slight light.
3. Look at luster. Waxy/dull when rough, high glassy polish when finished.
4. Test hardness. It scratches glass and steel (Mohs ~6.5–7).
5. Inspect the break. Smooth conchoidal fracture with no cleavage.
6. Feel and weigh. Dense, smooth, and cool — typical of solid chalcedony.

Key Diagnostic Tests

• Hardness: 6.5–7 (quartz family). Scratches glass; a knife will not scratch it.
• Streak: White.
• Fracture: Conchoidal, no cleavage.
• Density: ~2.6 g/cm³.
• No acid reaction, non-magnetic, opaque.
• Diagnostic feature: Earthy snakeskin/wavy banded pattern in opaque chalcedony.

Common Look-Alikes and How to Tell Them Apart

• Other patterned jaspers (e.g., picture, polychrome, ocean jasper): All share the same quartz properties; cobra jasper is distinguished by its specific flowing snakeskin banding. Pattern, not chemistry, is the differentiator.
• Banded agate: Agate is translucent with crisp concentric bands; cobra jasper is opaque with earthy, irregular wavy patterns.
• Petrified wood: May show grain and cell structure; cobra jasper lacks woody cellular texture.
• Serpentine: Much softer (2.5–4), scratched by a knife, often greasy-feeling and greenish; cobra jasper is hard (6.5–7).
• Chert/flint: Generally duller and more uniform, lacking the distinctive flowing banded pattern.

Where It Is Found

Cobra jasper, like most decorative jaspers, originates from silica-rich sedimentary and volcanic settings where iron-bearing chalcedony filled or replaced host rock. Much commercial material comes from India and Madagascar, with other jaspers from Australia, Brazil, and the western United States. Look in jasper-bearing gravels, weathered volcanic terrains, and lapidary rough markets.