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; displays multicolor agate or jasper replacement with preserved cellular wood structures; vitreous to waxy luster.

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Physical properties

Hardness of 7 on the Mohs scale; displays multicolor agate or jasper replacement with preserved cellular wood structures; vitreous to waxy luster.

Formation & geological history

Formed through permineralization where groundwater rich in dissolved silica replaces organic wood tissue over millions of years.

Uses & applications

Used primarily for ornamental carvings, polished display slabs, jewelry, and by fossil collectors.

Geological facts

The Petrified Forest National Park in Arizona contains one of the world's largest concentrations of high-quality petrified wood dating to the Triassic period.

Field identification & locations

Identify by retaining the external or internal microscopic grain and growth rings of ancient trees while feeling as heavy and hard as quartz.

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