Rock Identifier
Petrified Wood (Silicified Wood (SiO2)) — fossil
fossil

Petrified Wood

Silicified Wood (SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on Mohs scale; colors vary including brown, grey, black, and red; vitreous to waxy luster; cryptocrystalline quartz structure with preserved cellular wood grain.

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Physical properties

Hardness of 7 on Mohs scale; colors vary including brown, grey, black, and red; vitreous to waxy luster; cryptocrystalline quartz structure with preserved cellular wood grain.

Formation & geological history

Formed when buried organic wood is slowly replaced by silica-rich groundwater over millions of years, typically in sedimentary basins.

Uses & applications

Used in ornamental carvings, high-end lapidary work, custom furniture tops, and prized by mineral collectors.

Geological facts

Famous occurrences include Arizona's Petrified Forest National Park, where entire Triassic forests transformed into solid quartz.

Field identification & locations

Identified by retaining visible tree rings and wood texture while possessing the heavy weight and extreme hardness of quartz; found globally.

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