Rock Identifier
Petrified Wood (Silicified Wood) — fossil
fossil

Petrified Wood

Silicified Wood

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, features varied earth-tone colors like brown, red, and yellow with a vitreous to waxy luster. Retains the original cellular structure of the wood transformed into microcrystalline quartz.

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Physical properties

Hardness of 7 on the Mohs scale, features varied earth-tone colors like brown, red, and yellow with a vitreous to waxy luster. Retains the original cellular structure of the wood transformed into microcrystalline quartz.

Formation & geological history

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

Uses & applications

Used primarily in lapidary arts, decorative objects, jewelry, and prized by fossil and mineral collectors.

Geological facts

The petrification process preserves microscopic cellular details of ancient flora dating back hundreds of millions of years. Famous deposits include the Petrified Forest National Park in Arizona.

Field identification & locations

Identify by visible growth rings and bark texture combined with a conchoidal fracture and high hardness that scratches glass. Commonly found in sedimentary layers associated with ancient volcanic ash beds.

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