Rock Identifier
Petrified Wood (Silicified Wood (SiO2)) — fossil
fossil

Petrified Wood

Silicified Wood (SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, variable earth-tone colors, vitreous to waxy luster, and amorphous crystal structure.

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Physical properties

Hardness of 7 on the Mohs scale, variable earth-tone colors, vitreous to waxy luster, and amorphous crystal structure.

Formation & geological history

Formed through permineralization where organic wood materials are gradually replaced by silica-rich groundwater over millions of years.

Uses & applications

Used for ornamental carvings, decorative tabletops, jewelry, and prized by fossil and mineral collectors.

Geological facts

Famous occurrences include the Petrified Forest National Park in Arizona, featuring logs dating back over 200 million years to the Triassic period.

Field identification & locations

Identified by retaining the original cellular wood grain structure combined with conchoidal fractures typical of quartz; found worldwide in sedimentary deposits.

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