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, waxy to vitreous luster, amorphous crystal structure, and coloration ranging from brown to white due to mineral substitution.

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Physical properties

Hardness of 7 on the Mohs scale, waxy to vitreous luster, amorphous crystal structure, and coloration ranging from brown to white due to mineral substitution.

Formation & geological history

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

Uses & applications

Used in lapidary arts, ornamental carvings, high-end jewelry, and as decorative display specimens.

Geological facts

Famous occurrences include the Petrified Forest National Park in Arizona, featuring logs dating back over 200 million years.

Field identification & locations

Identify by retaining the original cellular wood grain structure combined with conchoidal fracture and high hardness. Found worldwide in sedimentary rock layers.

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