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Agate
1-443.40.00Name: derived from its occurrence at the Achates River in southwestern Sicily.
Clades: variety of Chalcedony; uartzes; Tectosilicates; Silicates; Lapidae.
Chemical: SiO2.
Crystal system: Trigonal or Monoclinic.
Color: colorless, gray, red, white, any color due to embedded minerals, multicolored specimen not uncommon.
Lustre: waxy, dull.
Hardness: 6½ to 7.
Specific gravity: 2.6.
Clades: variety of Chalcedony; uartzes; Tectosilicates; Silicates; Lapidae.
Chemical: SiO2.
Crystal system: Trigonal or Monoclinic.
Color: colorless, gray, red, white, any color due to embedded minerals, multicolored specimen not uncommon.
Lustre: waxy, dull.
Hardness: 6½ to 7.
Specific gravity: 2.6.