fossil

Petrified Wood

Silicified wood (Quartz pseudomorph after wood)

Hardness: 6.5-7 (Mohs scale); Color: Brown, grey, tan, and reddish hues; Luster: Dull to waxy; Texture: Preserved wood grain and fibrous structure; Cleavage: None (conchoidal fracture).

Hardness: 6
Color: Brown, grey, tan, and reddish hues
Luster: Dull to waxy

Identified July 5, 2026More fossil →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Brown, grey, tan, and reddish hues; Luster: Dull to waxy; Texture: Preserved wood grain and fibrous structure; Cleavage: None (conchoidal fracture).

Formation & geological history

Formed through permineralization where organic wood materials are replaced by minerals (usually silica/quartz) over millions of years, often in volcanic ash beds or sedimentary basins dating from the Paleozoic to Cenozoic eras.

Uses & applications

Used primarily as decorative garden stones, lapidary material for jewelry (cabochons), furniture (tabletops), and as educational fossil specimens.

Geological facts

The entire structure of the original plant is often preserved down to the microscopic level. Arizona's Petrified Forest National Park is one of the most famous localities in the world, containing trees from the Triassic period.

Field identification & locations

Identify by looking for characteristic bark-like textures or growth rings on a material that feels like stone and cannot be scratched by a steel knife. Common in areas with a history of volcanic activity and sedimentary deposition.

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