Rock Identifier
Petrified Wood (Silicified wood (Quartz/Chalcedony, SiO2)) — fossil
fossil

Petrified Wood

Silicified wood (Quartz/Chalcedony, SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, vitreous to dull luster, cryptocrystalline structure, displays preserved cellular wood grain with colors from iron and manganese oxides.

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to dull luster, cryptocrystalline structure, displays preserved cellular wood grain with colors from iron and manganese oxides.

Formation & geological history

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

Uses & applications

Used in decorative lapidary work, jewelry, bookends, and collected as a natural fossil specimen.

Geological facts

Famous occurrences 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 combining the external weight and hard quartz feel of stone with distinctly visible tree rings and cellular grain patterns.

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