sedimentary
Banded Agate
Agate (Silicon Dioxide, SiO2)
Hardness: 6.5-7 Mohs; Color: Brown, grey, white with banding; Luster: Waxy to vitreous; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.6.
- Hardness
- 6
- Color
- Brown, grey, white with banding
- Luster
- Waxy to vitreous
Identified More sedimentary →
Explore Banded Agate in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 Mohs; Color: Brown, grey, white with banding; Luster: Waxy to vitreous; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.6.
Formation & geological history
Formed as a secondary mineral in volcanic or metamorphic rocks, often within cavities (geodes) where silica-rich fluids deposit layers of chalcedony over time.
Uses & applications
Used in ornamental jewelry, tumbled stones, decorative carvings, and industrially for mortars and pestles due to its hardness and chemical resistance.
Geological facts
Agate is a variety of chalcedony. The name comes from the Achates River in Sicily, where agates were first discovered in ancient times.
Field identification & locations
Look for distinctive color banding and a translucent or waxy appearance. Common in riverbeds and volcanic areas across Brazil, USA, and India.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Cone-in-cone structure (Limestone)
Cone-in-cone structure (Secondary Sedimentary Structure)
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary