Stone Mania

Chalcedony (kal SED uh nee) is one of the cryptocrystalline varieties of the mineral quartz meaning any form of quartz whose crystals are too small to be seen without high magnification. 

Chalcedony has a waxy lustre, it may be semi-transparent or translucent and is usually white to grey, greyish-blue or some shade of brown.  Chalcedony can also be virtually black.  Only the translucent single coloured types are known as chalcedony whereas the rest of this group are known by individual variety names or as jasper or agate.

Clear red chalcedony is known as carnelian, the green variety which is coloured by nickel oxide is chrysoprase and onyx is black and white banded chalcedony.  Plasma is bright to emerald green and chalcedony with small red spots of jasper is known as bloodstone.

The various types of chalcedony differ in colour due to metallic impurities such as iron, nickel, copper and titanium which are present during crystallization.

Throughout history, mankind has valued gemstones and minerals for practical, mythical, and aesthetic reasons. The practical uses of minerals probably dominated in the past just as they do today.  Archaeological evidence from Olduvai Gorge in Tanzania suggests that man's tool-making ability may date back more than 2 million years, starting with primitively chipped pebble tools.  Chalcedony arrow and spear heads (dating as far back as forty thousand years) have been found at later sites all over North America, as well as in France, Egypt, and other North African countries. These tools allowed our ancient ancestors to hunt and kill much larger mammals, such as the mastodon. 

Because of its abundance, durability and beauty, chalcedony was except for sticks, animal skins, bones, plain rocks and possibly obsidian, the earliest raw material used by man.

The earliest recorded use of chalcedony was for projectile points, knives, tools, and containers such as cups and bowls.  Early man made weapons and tools from many different varieties of chalcedony including agate, flint, jasper and petrified wood. The move from using certain items as weapons and tools to using the same items for ceremonial and personal adornment is very easily made.  It was only natural for early man to use his finest looking knife for special occasions or to attach a special lance point or arrowhead to his tunic.  In fact agate and petrified wood may have simply been elevated to gemstones from common and functional weapons or tools.

Chalcedony was used as a sacred stone by the native American indians promoting stability within the ceremonial activities of the tribes. 

In crystal healing, chalcedony is believed to banish fear, hysteria, depression, mental illness and sadness.  Wearing a piece of chalcedony is said to be beneficial for the eyes and for promoting calmness and tranquillity.  Chalcedony is also believed to stimulate creativity.  Its energies are soothing and stabilizing, it enhances mental stability, promotes inner peace and emotional honesty and dispels the negative energies that manifest as anger.  Chalcedony can also balance the energy of the body, mind, emotions and spirit.  It is also believed to be effective for the elimination of negative influences that can cause bad dreams.

Chalcedony is found in many parts of the world but the most prized gemstones come from India, Madagascar, Burma, Brazil, Mexico & USA.

Chalcedony is graded 6.5 to 7 on Mohs scale of mineral hardness.

The following links offer further reading on chalcedony

http://en.wikipedia.org/wiki/Chalcedony
http://www.gemologyonline.com/chalcedony.html