gemstone
Agate
SiO2 (Silicon Dioxide)
Hardness of 6.5 to 7 on the Mohs scale, colors vary widely including brown, white, and tan with a waxy to vitreous luster, cryptocrystalline quartz structure, conchoidal fracture.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, colors vary widely including brown, white, and tan with a waxy to vitreous luster, cryptocrystalline quartz structure, conchoidal fracture.
Formation & geological history
Formed primarily within cavities of volcanic and metamorphic rocks through the slow deposition of silica-rich groundwater over millions of years.
Uses & applications
Used in jewelry, ornamental carvings, decorative objects, and for industrial grinding mortars due to its hardness.
Geological facts
Agates are among the most popular stones for tumbling and lapidary work because of their durability and striking banded patterns.
Field identification & locations
Identified by its waxy luster, hardness that scratches glass, and characteristic translucent to opaque patterns. Found globally in volcanic regions.
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