mineral
Tumbled honey-brown chalcedony (likely agate)
Microcrystalline quartz, SiO₂; chalcedony, possibly iron-stained agate
AI-generated identification · may be incorrectRounded, polished, mottled golden-brown and gray with a waxy-to-glassy luster. Quartz hardness is 6.5–7 Mohs; trigonal crystal structure at the microscopic scale, with no visible cleavage and conchoidal fracture.
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Physical properties
Rounded, polished, mottled golden-brown and gray with a waxy-to-glassy luster. Quartz hardness is 6.5–7 Mohs; trigonal crystal structure at the microscopic scale, with no visible cleavage and conchoidal fracture.
Formation & geological history
Silica-rich fluids deposited quartz in rock cavities or fractures; iron oxides can create the brown and yellow coloration. The specimen’s geological age and exact source cannot be determined from the image.
Uses & applications
Tumbled chalcedony and agate are used in jewelry, ornaments, and lapidary collections; chalcedony also has limited industrial uses.
Geological facts
Agate is banded chalcedony, but banding is not clearly visible here, so the exact variety is uncertain.
Field identification & locations
Look for a hard, compact silica stone, waxy luster, and conchoidal fracture; agate may show distinct bands when held to light. Chalcedony occurs worldwide, commonly in volcanic rocks and sedimentary deposits.
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