Crystal system: Hexagonal.
Cell Salt: Silicon dioxide.
Colour: White to grey, brown, blue, black; clear red to brownish red (cornelian); bright green with red spots (Bloodstone/Heliotrope); variegated and banded (Agate); with mosslike or treelike inclusions (Moss Agate); apple-green (Chrysoprase); variegated and mottled red, yellow, brown (Jasper); whitish, dull grey, smoky brown to black (Flint) green-onyx.
Energy: Electric.
Element: Air and fire.
Planet/Sign: Mercury/Virgo; Jupiter/Sagittarius.
Uses: In general, Chalcedony gives success in lawsuits, good health, safe travels and protects against harmful spirits. However, there are many varieties of Chalcedony crystals, each with its own particular properties.