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, colors range from pale tan and brown to multicolored hues depending on mineral impurities, vitreous to waxy luster, amorphous crystal structure (microcrystalline quartz)

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Physical properties

Hardness of 6.5 to 7 on the Mohs scale, colors range from pale tan and brown to multicolored hues depending on mineral impurities, vitreous to waxy luster, amorphous crystal structure (microcrystalline quartz)

Formation & geological history

Formed when plant material is buried by sediment in anoxic conditions and groundwater rich in dissolved silica replaces the organic matter cell by cell over millions of years

Uses & applications

Used in ornamental objects, lapidary arts, jewelry, bookends, and prized by fossil and rock collectors

Geological facts

The petrification process preserves the original cellular structure of the wood down to microscopic details, sometimes even preserving tree rings

Field identification & locations

Identified by its woody grain texture combined with stone-like weight and hardness; found worldwide in sedimentary deposits associated with ancient forests and volcanic ash beds

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