Rock Identifier
Petrified Wood (Silicified Wood (SiO2)) — fossil
fossil

Petrified Wood

Silicified Wood (SiO2)

AI-generated identification · may be incorrect

Hardness of 6.5 to 7 on the Mohs scale, vitreous to waxy luster, amorphous crystal structure, and exhibits preserved cellular wood grain patterns in brown, grey, and red tones.

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Physical properties

Hardness of 6.5 to 7 on the Mohs scale, vitreous to waxy luster, amorphous crystal structure, and exhibits preserved cellular wood grain patterns in brown, grey, and red tones.

Formation & geological history

Formed through permineralization, where organic wood material is buried under sediment and progressively replaced by silica-rich groundwater over millions of years.

Uses & applications

Used for decorative ornaments, lapidary art, jewelry, and high-end display specimens for collectors.

Geological facts

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

Field identification & locations

Identified by its distinctive weight, conchoidal fracture like quartz, and visible microscopic wood grain structure; globally distributed in sedimentary layers.

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