mineral
Chalcedony / milky quartz flake
Microcrystalline quartz (SiO₂), likely chalcedony; possibly a worked quartzite or chert fragment
AI-generated identification · may be incorrectCream to translucent white, waxy-to-dull luster, conchoidal fracture, no visible cleavage; quartz hardness about 7 Mohs and specific gravity about 2.60–2.65. The tapered, symmetrical form and flake scars suggest intentional knapping rather than a natural crystal.
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Physical properties
Cream to translucent white, waxy-to-dull luster, conchoidal fracture, no visible cleavage; quartz hardness about 7 Mohs and specific gravity about 2.60–2.65. The tapered, symmetrical form and flake scars suggest intentional knapping rather than a natural crystal.
Formation & geological history
Silica-rich groundwater formed chalcedony in cavities or fractures, commonly in volcanic or sedimentary rocks; the pictured piece appears human-worked, with age indeterminate. Around 43°N, 108°W, quartz/chert and silicified volcanic rocks are regionally plausible.
Uses & applications
Historically suitable for a stone tool or arrowhead; chalcedony is also used for beads, carvings, abrasives, and ornamental objects. A clear archaeological provenance can greatly increase value.
Geological facts
The pointed shape and bifacial-looking flaking may indicate a small lithic point or blade, but the image alone cannot establish whether it is prehistoric or recently made.
Field identification & locations
Inspect the edges for deliberate, repeated flake scars and a striking platform; natural breakage is usually less patterned. Common regional possibilities include chalcedony, jasper, and siliceous chert from Wyoming’s sedimentary and volcanic terrains; avoid damaging it if archaeological context is possible.
