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Agate alphabet
Gemological data
- Chemical formula : SiO2
- Hardness (Mohs) : 6.5/7
- Density : 2.60
- Refractive index : 1.53 - 1.54
- Birefingence : 0.004 - 0.009
- Crystal system : Rhomboedric - Trigonal
- Group : Quartz
The gallery
It is a variety of agate containing iron oxides. Depending on the size of the cabochons, shapes and letters are highlighted.
Here is a complete alphabet!
To learn more about the mineralogy of the agate, see Mindat.ord
