Chalcedony in its banded form is called agate. Also included are translucent chalcedony varieties such as moss agate, dendritic agate, and phenomenal varieties like fire agate and iris agate. Decorative items, beads, cabochons, and cameos have all been carved from agate for years. The name agate comes from the river Achates (now Dirillo) in southwest Sicily, where it was first discovered.
As a folkloric medicine, agate has been used to treat snake stings and scorpion stings. According to some Native American tribes, it could strengthen the body and calm the spirit. Ancient Egyptians believed that agate quenched thirst and protected against lightning. As many folkloric beliefs exist as there are patterns in the stone touting agate's "powers."
The ancient Chinese credited agate for bringing prosperity and luck and for energizing the chi of the wearer. One thing is for sure: agate is a wonderful stone!
Hardness
6.5-7
Specific Gravity
2.550-2.700 Typical:2.600
Toughness
Excellent
Luster
Greasy, Vitreous
Stability
Good
Fracture
Conchoidal, Granular
Cleavage
None