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 a vitreous to dull luster. Displays preserved cellular wood structures in varying colors like gray, brown, and red.

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Physical properties

Hardness of 7 on the Mohs scale with a vitreous to dull luster. Displays preserved cellular wood structures in varying colors like gray, brown, and red.

Formation & geological history

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

Uses & applications

Used primarily in decorative items, lapidary arts, jewelry, and as collector specimens.

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 its woody exterior texture combined with a stone-like weight and conchoidal fracture. Found worldwide in ancient sedimentary layers and volcanic ash beds.

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