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. Varies in color from brown and gray to red and yellow depending on mineral impurities. Luster is vitreous to dull with a microcrystalline quartz crystal structure.

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Physical properties

Hardness of 7 on the Mohs scale. Varies in color from brown and gray to red and yellow depending on mineral impurities. Luster is vitreous to dull with a microcrystalline quartz crystal structure.

Formation & geological history

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

Uses & applications

Used primarily for decorative items, lapidary art, jewelry, and as collector specimens.

Geological facts

The petrification process can preserve microscopic cellular structures of the original ancient trees down to the annual growth rings.

Field identification & locations

Identified by retaining the exterior texture or growth rings of wood combined with a high density and conchoidal fracture typical of quartz. Commonly found in regions with ancient volcanic ash deposits.

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