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, earthy to vitreous luster, amorphous quartz structure, and preserved cellular wood grain coloration ranging from brown to grey.

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Physical properties

Hardness of 7 on the Mohs scale, earthy to vitreous luster, amorphous quartz structure, and preserved cellular wood grain coloration ranging from brown to grey.

Formation & geological history

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

Uses & applications

Used primarily in decorative items, lapidary arts, high-end jewelry, and as educational or display specimens for fossil collectors.

Geological facts

The petrification process preserves microscopic cellular structures of the original wood, sometimes capturing details from the Triassic period or older.

Field identification & locations

Identify in the field by heavy weight, conchoidal fracture, and visible ring or grain patterns that feel like stone rather than wood. Common worldwide.

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