sedimentary
Petrified Wood
Silicified wood (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, varied Earth-tone colors like brown, red, and yellow, vitreous to dull luster, and cryptocrystalline quartz structure.
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Physical properties
Hardness of 7 on the Mohs scale, varied Earth-tone colors like brown, red, and yellow, vitreous to dull luster, and cryptocrystalline quartz structure.
Formation & geological history
Formed over millions of years when buried organic wood is replaced mineral-by-mineral by silica-rich groundwater in anoxic conditions.
Uses & applications
Used for decorative objects, lapidary arts, jewelry, and prized by fossil and mineral collectors.
Geological facts
The cellular structure of the original tree is often perfectly preserved, allowing scientists to identify ancient plant species.
Field identification & locations
Identified by retaining the distinct grain and growth rings of wood despite having the weight and hardness of quartz; commonly found in river deposits and volcanic ash beds.
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