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; colors range from brown and gray to red and yellow; vitreous to dull luster; cryptocrystalline quartz structure.

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Physical properties

Hardness of 7 on the Mohs scale; colors range from brown and gray to red and yellow; vitreous to dull luster; cryptocrystalline quartz structure.

Formation & geological history

Formed over millions of years when buried plant material is slowly replaced by silica-rich groundwater in sedimentary environments.

Uses & applications

Used in decorative items, lapidary arts, jewelry, and prized by fossil collectors.

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 wood grain and cellular structure while possessing the high hardness and weight of quartz; found worldwide in ancient sedimentary strata.

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