sedimentary
Agate Nodule
Silicon dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, waxy luster, conchoidal fracture, and microcrystalline quartz structure with multicolored banding.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy luster, conchoidal fracture, and microcrystalline quartz structure with multicolored banding.
Formation & geological history
Formed in cavities of volcanic or sedimentary rocks through the slow deposition of silica-rich groundwater over millions of years.
Uses & applications
Widely used in ornamental carvings, jewelry, lapidary arts, and sought after by mineral collectors.
Geological facts
Agate is a variety of chalcedony that often forms in ancient gas bubbles within volcanic lava flows, preserving distinct environmental timelines in its bands.
Field identification & locations
Easily identified by its distinct concentric color bands, waxy texture, and extreme hardness that easily scratches glass. Commonly found globally in volcanic regions.
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Sandstone or Siltstone
Arenite (if sandstone)
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Sandstone
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Shale
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Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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