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, varied multicolored hues of red, brown, yellow, and grey, vitreous to waxy luster, and cryptocrystalline quartz structure.

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Physical properties

Hardness of 7 on the Mohs scale, varied multicolored hues of red, brown, yellow, and grey, vitreous to waxy luster, and cryptocrystalline quartz structure.

Formation & geological history

Formed when buried organic wood is slowly replaced by silica-rich groundwater over millions of years.

Uses & applications

Used in ornamental carvings, decorative lapidary items, custom furniture, and sought after by fossil and mineral collectors.

Geological facts

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

Field identification & locations

Identified by preserved annual growth rings and cellular wood grain structures combined with the heavy weight and hardness of quartz.

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