
sedimentary
Chert / Flint Arrowhead
Microcrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, white to grayish color, crypto-crystalline structure, no cleavage, specific gravity around 2.60.
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Physical properties
Hardness of 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, white to grayish color, crypto-crystalline structure, no cleavage, specific gravity around 2.60.
Formation & geological history
Formed through the chemical replacement of limestone or chalk by silica-rich groundwater in marine environments, typically over millions of years.
Uses & applications
Historically used by indigenous peoples for making tools, spear points, and arrowheads due to its sharp conchoidal fracture when knapped. Also valued as an artifact by collectors.
Geological facts
This specimen is an example of lithic reduction, showing human craftsmanship on a naturally occurring sedimentary rock. Flint and chert were vital for survival in prehistoric times for fire-starting and hunting.
Field identification & locations
Can be identified by its sharp edges, conchoidal fracture patterns from flaking, and waxy luster. Commonly found in areas with historical indigenous presence, creek beds, and plowed fields where agricultural activity disturbs the soil.
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