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 with variable colors including brown, yellow, and red. Exhibits a vitreous to waxy luster and cryptocrystalline structure.

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Physical properties

Hardness of 7 on the Mohs scale with variable colors including brown, yellow, and red. Exhibits a vitreous to waxy luster and cryptocrystalline structure.

Formation & geological history

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

Uses & applications

Used extensively in ornamental carvings, jewelry, lapidary arts, and as high-demand decorative display pieces for 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

Identify by retaining the original cellular wood grain structure combined with conchoidal fracture and glass-like hardness. Common worldwide.

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