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; colors range from brown and yellow to red and black; vitreous to waxy luster with preserved cellular wood grain structures.

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Physical properties

Hardness of 7 on the Mohs scale; colors range from brown and yellow to red and black; vitreous to waxy luster with preserved cellular wood grain structures.

Formation & geological history

Formed when buried tree logs are slowly replaced by silica-rich groundwater over millions of years.

Uses & applications

Used for decorative items, gemstone jewelry, lapidary carvings, and as educational display specimens.

Geological facts

Petrified wood retains the exact cellular structure of the ancient trees, sometimes dating back over 200 million years to the Triassic period.

Field identification & locations

Identified by its woody exterior texture combined with a heavy, stone-like weight and conchoidal fracture. Commonly found in deserts, riverbeds, and sedimentary rock formations worldwide.

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