Rock Identifier
Petrified Wood (Silicified wood (Quartz, SiO2)) — fossil
fossil

Petrified Wood

Silicified wood (Quartz, SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, vitreous to dull luster, brown and tan coloration, and amorphous crystal structure with preserved cellular wood grain.

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to dull luster, brown and tan coloration, and amorphous crystal structure with preserved cellular wood grain.

Formation & geological history

Formed via permineralization when buried tree logs are saturated with silica-rich groundwater over millions of years.

Uses & applications

Used primarily in decorative lapidary work, jewelry, bookends, and as collector specimens.

Geological facts

The organic material is completely replaced by minerals while retaining the original microscopic cellular structure of the tree.

Field identification & locations

Identify by its distinct wood-like grain patterns combined with a heavy, stone-like feel and conchoidal fracture. Commonly found in alluvial deposits and badlands worldwide.

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