Mineral

Agate

SiO2 (Silicon Dioxide)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on the Mohs scale. Color: Highly variable, this specimen is brownish-orange. Luster: Waxy to vitreous. Crystal structure: Cryptocrystalline (microcrystalline quartz). Cleavage: None, exhibits conchoidal fracture.

Hardness: 6
Color: Highly variable, this specimen is brownish-orange
Luster: Waxy to vitreous

Identified August 25, 2026More mineral →

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Physical properties

Formation & geological history

Forms primarily in cavities of eruptive rocks or ancient lavas. Silica-rich fluids percolate through the rock, depositing layers of microcrystalline quartz over time.

Uses & applications

Often used in lapidary work, jewelry, and ornamental carving. Also popular among rock collectors and for tumbling.

Geological facts

Agate is characterized by its fineness of grain and variety of color. The colors are often arranged in alternating bands, which can be straight, wavy, or concentric.

Field identification & locations

Identified by its waxy luster, hardness (cannot be scratched by a knife), and often by its banding (though not all agates are strongly banded). Commonly found in volcanic areas, riverbeds, and beaches.