Chalcedony

Hardness (Mohs): 7
Color: Blue to Lavender; White to gray, brown, black; orange; clear red to brownish red (Carnelian); bright green with red spots (Bloodstone); variegated and banded (Agate); with moss like or treelike inclusions (Moss or Dendritic Agate); green (Chrysoprase); whitish, dull gray, smoky brown to black (Flint)
Transparency: Transluscent to Transparent
Notable Occurrences: Found Worldwide, including the United States

Quartz is divided into two classifications - crystalline and micro-crystalline (also known as cryptocrystalline), and chalcedony is a group of micro-crystalline quartzes which includes agate, chrysoprase, heliotrope, fossillized wood, jasper, carnelian, onyx and the specific stone referred to as chalcedony - while chalcedony is a group name, it also is the name of a particular stone within that group. While the atoms in crystalline quartzes are crystals, the micro-crystalline quartzes are composed of layers fiber which often contain water or air between the layers. Because of this, chalcedony is pourous and can be dyed. The micro-crystaline quartzes are divided into two groups, jasper and chalcedony, with the jaspers tending to be opaque and the chalcedonies being more translucent or transparent. The specific stone called chalcedony is generally the blue variety and has no layering or banding of color. Most other colors of chalcedony are specifically named stones, such as green chalcedony, which is chrysoprase. Among the blue chalcedonies, the bright powder blue colors are highly prized. A light blue shade of chalcedony is referred to as Blue Mist Chalcedony. Also prized is a pure orange chalcedony which does not have the redness of carnelian. The hardness and durabilty of chalcedony makes it a well-suited for jewelry.

Folklore/Metaphysical Properties: In the past, chalcedony has been used during ceremonial activities by some native americans to promote stability, and by sailors to protect against drowning. It is considered a useful stone for balancing the energy of the body, mind, emotions and spirit. It is said to give success in lawsuits; help provide safe travel; protect against harmful spirits; help overcome jealousy and despair; bring love and comfort; dispel anger; and, as with many of the blue stones, promote awareness and clearer psychic vision. Within the many varieties of the group chalcedony, each stone has its own particular properties - such as Agate, Bloodstone, Carnelian, Chrysoprase, Fire Agate, Moss Agate, etc.