Agate
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| Agate | |
|---|---|
 |
|
| Moss agate pebble, 2.5 cm (1 inch) long | |
| General | |
| Category | Quartz variety |
| Chemical formula | Silica, SiO2 |
| Identification | |
| Color | White to grey, light blue, orange to red, black. |
| Crystal habit | Cryptocrystalline silica |
| Crystal system | Rhombohedral Microcrystalline |
| Cleavage | None |
| Fracture | Conchoidal with very sharp edges. |
| Mohs Scale hardness | 7 |
| Luster | Waxy |
| Refractive index | 1.530-1.540 |
| Birefringence | up to +0.004 (B-G) |
| Pleochroism | Absent |
| Streak | White |
| Specific gravity | 2.58-2.64 |
Agate is a kind of quartz and it is a mineral. Agate can come in many different kinds and colors.
