gemstone
Agate
Silicon Dioxide (Chalcedony), SiO2
Hardness: 6.5-7 on the Mohs scale, Color: various bands of white, grey, blue, red, green, and brown, Luster: waxy to vitreous, Crystal structure: trigonal/microcrystalline, Cleavage: none, Specific gravity: 2.58-2.64
- Hardness
- 6
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Physical properties
Hardness: 6.5-7 on the Mohs scale, Color: various bands of white, grey, blue, red, green, and brown, Luster: waxy to vitreous, Crystal structure: trigonal/microcrystalline, Cleavage: none, Specific gravity: 2.58-2.64
Formation & geological history
Formed mainly in cavities of volcanic and metamorphic rocks by the deposition of silica from groundwater solutions in rhythmic layers.
Uses & applications
Used for jewelry, ornamental objects, carvings, and as a collector's specimen.
Geological facts
Agate is one of the most popular materials used in art carving and was widely used in ancient times for seals and signet rings.
Field identification & locations
Easily identified by its distinctive banded patterns and translucent quality. Found globally, especially in regions with ancient volcanic activity.
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