Monday, June 7, 2010

Pietersite

Gemstone :
Pietersite

Birthstone Month :
Pietersite is not associated with any particular birthstone month.

Zodiac :
Pietersite is associated with the zodiac sign of Leo.

Chemical Symbol :
SiO2

Chemical Make-up :
Pietersite is a pseudomorph variety of Quartz. Pseudomorph is classified as a mineral having the outward appearance of another mineral that it has replaced by chemical action. Pietersite consists of closely packed Crocidolite fibers that have been replaced by colorless macrocrystalline Quartz.

History & Lore :
There is not 100% agreement regarding the exact origins of the name Quartz, but the two most widely accepted opinions are that the word Quartz is derived from the Greek 'krystallos', meaning “ice”, or the German 'quarz'.

Pietersite was first discovered in Namibia in 1962, where it was named after its discoverer, Sid Pieters.

Some of the earliest primitive tools fashioned by man some 2.5 million years ago, and discovered in the Omo valley in Ethiopia were made of Quartz. It is believed that Quartz was used because of its hardness and isotropic brittleness that made the fashioning of the tools relatively easy.

Chipped flint projectile points used for fire-making have been found on Mousterian sites in western Europe that date back around 40,000 years.

In addition to its use in tool-making, certain varieties of Quartz were used for divination. Spherical Quartz rock crystals were often shaped into crystal balls and used for disease diagnosis and awareness of events occurring in distant places.

More recently there was major production of synthetic Quartz during World War II. This synthetic Quartz was used to supply crystals for radios.

Today, Quartz is not only used for gemstone purposes, but also as a raw chemical ingredient in the manufacturing of abrasives, cements, concrete, porcelain, glass, and many other industrial materials.

Because of its piezoelectric and pyroelectric properties, Quartz is commonly used in the production of watches, clocks, computers, and radios.

Pietersite is said to hold the “keys to the kingdom of heaven”, as it is believed to dispel illusion and assist the wearer in the recognition of the beauty of the soul. It is believed to help us be true to ourselves and give loving guidance.

Availability :
Pietersite is a rare gemstone, although it is priced moderately in comparison with other Cat's Eye gemstones.

Sources :
The two major sources of Pietersite are Namibia and the Henan Province of China.

Evaluation :
Pietersite is rated at 6.5 to 7 on Moh's Scale of Hardness. The pseudomorphism begins when Quartz becomes embedded between the fibers of the Crocidolite (Crocidolite is a blue mineral composed of Iron and Sodium, more commonly known as a form of Asbestos). During the transformation, the Crocidolite is completely dissolved, with the Quartz taking on its fibrous formations. This creates parallel lines within the gem which allows the play of light and movement, known scientifically as chatoyancy. The play of light that rolls across the surface is reminiscent of the eye of a cat.

Even though the Iron and Sodium dissolves, traces of hydrated oxide can still be found within the stone. The varying amounts of hydrated oxide of iron can actually cause several colors and/or mixes of colors rather then the initial blue color of Crocidolite. The colors of Pietersite include blues, rusty reds, golds, and browns. The blues tend to be the most dominant and can be found in a vast array of hues from baby blue to a dark midnight blue. The surface of a Pietersite gemstone is quite intriguing as the colors are formed in streaks and swirls in every direction.

The most important factors when evaluating the value of a Pietersite is the level of chatoyancy displayed and the beauty of the color and patterns in which were formed.

Common Cuts :
Pietersite is most commonly and almost exclusively cut into cabochons. This is because a tall, round cut is required to maximize the chatoyancy effect most brilliantly. The orientation of the cut is critical with Pietersitee as it must be cut exactly parallel to the length of the fibers. If the cut is but a little off, the stone will end up lifeless, with little or no chatoyancy and no play of color.

Routine Enhancements :
There are no known enhancements for Pietersite.

Care & Cleaning :
Pietersite is best cleaned simply by polishing the stone with a soft cloth. As with most gemstones, Pietersite should be kept away from household chemicals and from prolonged exposure to extremes of heat as this can cause damage or permanent changes in coloration. Pietersite jewelry should be kept in a fabric-lined box away from other jewelry items in order to avoid scratching.

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