sedimentary
Petrified Wood
Silicified Wood (SiO2)
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, displays brownish or grey wood-grain patterns, vitreous to waxy luster, and amorphous crystal structure.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, displays brownish or grey wood-grain patterns, vitreous to waxy luster, and amorphous crystal structure.
Formation & geological history
Formed when buried organic wood is slowly replaced by silica-rich groundwater over millions of years.
Uses & applications
Used widely for decorative carvings, polished display specimens, jewelry, and lapidary arts.
Geological facts
Petrified wood retains the microscopic cellular structure of the original ancient trees, sometimes dating back over 200 million years.
Field identification & locations
Identify by its distinct wood-grain patterns combined with a hard, stone-like weight and glassy fracture; commonly found in riverbeds and arid badlands worldwide.
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