sedimentary
Petrified Wood
Silicified wood (SiO2)
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, variable colors due to mineral impurities, vitreous to waxy luster, amorphous crystal structure.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, variable colors due to mineral impurities, vitreous to waxy luster, amorphous crystal structure.
Formation & geological history
Formed through permineralization when buried organic material is slowly replaced by silica-rich groundwater over millions of years.
Uses & applications
Used for ornamental carvings, jewelry, display specimens, and lapidary art.
Geological facts
The cellular structure of the original tree is often perfectly preserved down to the microscopic level. Arizona's Petrified Forest contains some of the world's most vibrant specimens.
Field identification & locations
Identify by distinct wood grain patterns combined with conchoidal fracture and high hardness. Found globally in ancient sedimentary layers and volcanic ash beds.
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