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, vitreous to dull luster, colors range from brown and grey to multicolored, amorphous crystal structure with preserved cellular wood grain.

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to dull luster, colors range from brown and grey to multicolored, amorphous crystal structure with preserved cellular wood grain.

Formation & geological history

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

Uses & applications

Used for decorative objects, lapidary arts, jewelry, and educational or fossil collecting.

Geological facts

Famous occurrences include the Petrified Forest National Park in Arizona, where entire Triassic ecosystems are preserved in stone.

Field identification & locations

Identify by retaining the distinct texture of tree rings and bark while feeling unusually heavy and cold like glass or quartz.

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