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, multicolored due to mineral impurities, vitreous to waxy luster, amorphous crystal structure, lacks cleavage, and has a specific gravity of 2.5 to 2.7.

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Physical properties

Hardness of 7 on the Mohs scale, multicolored due to mineral impurities, vitreous to waxy luster, amorphous crystal structure, lacks cleavage, and has a specific gravity of 2.5 to 2.7.

Formation & geological history

Formed through permineralization where groundwater rich in dissolved silica replaces organic plant material over millions of years, often dating from the Triassic period or older.

Uses & applications

Used in decorative carvings, lapidary arts, high-end jewelry, custom furniture pieces, and as collector specimens.

Geological facts

Famous occurrences include the Petrified Forest National Park in Arizona, where entire ancient forests transformed completely into solid quartz.

Field identification & locations

Identified in the field by retaining original tree growth rings, bark texture, or wood grain while feeling exceptionally heavy and stone-like.

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