Jasper

Opaque, impurity-rich microcrystalline quartz. Iron oxides give the classic brick red, but jasper comes in nearly every earthy color and pattern.

Jasper specimen — Photo: Tommy from Arad, CC BY 2.0, via Wikimedia Commons

How to identify jasper

Completely opaque, even at thin edges.
Solid earthy colors, often red, sometimes patterned.
Hard — scratches glass.
Smooth, curved fracture surfaces.

Often confused with

Agate
Agate is translucent and banded; jasper blocks light.
Compare side by side
Rhyolite
Rhyolite often shows tiny crystals or flow bands and is a little softer and grainier.
Compare side by side

Where it's found

Oregon and Idaho
India
Madagascar
Arizona

Uses

Tumbled stones, beads and ancient seals and tools.

Rock tumbling

Great for tumbling.

Did you know?

Prehistoric people knapped jasper into blades because it breaks with a sharp edge, like flint.

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