sedimentary
Banded Agate
Cryptocrystalline Quartz (SiO2)
Hardness: 6.5-7 (Mohs), Color: Grey, white, and dark blue-grey bands, Luster: Waxy to vitreous, Structure: Microcrystalline, Cleavage: None (conchoidal fracture)
- Hardness
- 6
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Physical properties
Hardness: 6.5-7 (Mohs), Color: Grey, white, and dark blue-grey bands, Luster: Waxy to vitreous, Structure: Microcrystalline, Cleavage: None (conchoidal fracture)
Formation & geological history
Formed in cavities of volcanic rocks or ancient lavas, where silica-rich groundwater deposited layers of quartz over time.
Uses & applications
Commonly used for jewelry, lapidary art, ornaments, and as balancing stones in new-age practices.
Geological facts
Agate bands are formed through rhythmic crystallization cycles. This specific fragment appears to be a small tumbled or broken piece of a larger banded specimen.
Field identification & locations
Look for distinct color banding and a translucent quality when held to light. Often found in gravel beds or near volcanic sites.
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