sedimentary

Flint Arrowhead

Cryptocrystalline quartz (Chert/Flint, SiO2)

Hardness of 7 on the Mohs scale; dark grayish-brown to tan color with weathered cortex; waxy to vitreous luster; microcrystalline or cryptocrystalline structure; exhibits conchoidal fracture with sharp edges; specific gravity of approximately 2.60 to 2.65.

Identified August 4, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the replacement of calcium carbonate by silica in sedimentary rock environments (typically chalk or limestone formations) over millions of years. This specimen has been human-shaped (knapped) into an artifact.

Uses & applications

Historically used as a cutting tool, weapon projectile point, and for striking fire. Today, it is valued by artifact collectors and archaeologists.

Geological facts

Flint and chert were the primary materials used by prehistoric humans during the Stone Age to fashion tools and weapons due to its predictable conchoidal fracture, allowing for precise flaking.

Field identification & locations

Identified by its distinctive conchoidal fracture, sharp chipped edges indicating human modification, waxy luster, and hard microcrystalline quartz composition. Found globally wherever ancient tool-making cultures interacted with chert-bearing deposits.

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