sedimentary
Chert
Silicon Dioxide (Microcrystalline Quartz)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy or vitreous luster, conchoidal fracture, and colors ranging from white and gray to brown and tan.
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Physical properties
Hardness of 7 on the Mohs scale, waxy or vitreous luster, conchoidal fracture, and colors ranging from white and gray to brown and tan.
Formation & geological history
Forms through the chemical precipitation of silica-rich fluids or accumulation of siliceous skeletal remains in marine environments over millions of years.
Uses & applications
Historically used for making stone tools, arrowheads, and spark-striking fire starters.
Geological facts
Prehistoric humans heavily favored chert, often called flint when dark, for its sharp edges when fractured.
Field identification & locations
Identified by its distinctive waxy luster and conchoidal fracture; commonly found in limestone and chalk formations worldwide.
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