sedimentary
Petrified Wood
Silicified wood (SiO2)
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and preserves cellular wood structures in multicolored chalcedony or quartz.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and preserves cellular wood structures in multicolored chalcedony or quartz.
Formation & geological history
Formed when buried wood is slowly replaced by silica-rich groundwater under anoxic conditions over millions of years.
Uses & applications
Used in decorative items, lapidary arts, jewelry, furniture, and coveted by fossil collectors.
Geological facts
Complete ancient forests, such as the Petrified Forest in Arizona, have been preserved through this permineralization process dating back over 200 million years.
Field identification & locations
Identified by retaining tree ring patterns and bark texture while possessing the heavy weight and hardness of quartz; commonly found in sedimentary basins and volcanic ash layers worldwide.
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