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

Petrified Wood

Silicified wood (Quartz replacement, SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, colors range from grey to brown and multi-color, vitreous to dull luster, cryptocrystalline quartz structure.

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Physical properties

Hardness of 7 on the Mohs scale, colors range from grey to brown and multi-color, vitreous to dull luster, cryptocrystalline quartz structure.

Formation & geological history

Formed when buried wood is slowly replaced by minerals like silica in oxygen-depleted water 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, dating back over 200 million years to the Triassic period.

Field identification & locations

Identified by preserved cellular wood grain structures combined with stone-like weight and conchoidal fracture. Found worldwide in sedimentary deposits.

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