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

Petrified Wood

Silicified wood (SiO2)

AI-generated identification · may be incorrect

Hardness of 6.5-7 on the Mohs scale, variable colors including brown, black, and red, with a vitreous to waxy luster and cryptocrystalline quartz structure.

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Physical properties

Hardness of 6.5-7 on the Mohs scale, variable colors including brown, black, and red, with a vitreous to waxy luster and cryptocrystalline quartz structure.

Formation & geological history

Formed when buried vegetation is slowly replaced by silica-rich groundwater over millions of years, typically dating from the Triassic period and earlier.

Uses & applications

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

Geological facts

Petrified wood retains the original cellular structure of the ancient trees while completely transforming into solid stone.

Field identification & locations

Identify by visible wood grain combined with conchoidal fracture and high hardness that scratches glass; commonly found in arid regions and ancient riverbeds.

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