Monday, June 7, 2010

Indicolite

Gemstone:
Indicolite (Tourmaline)

This is the term used by experts to name Blue Tourmaline and simply means “blue stone”.

Birthstone Month:
Tourmaline is one of the two gemstones associated with the month of October.

Zodiac:
Being one of the two accepted birthstones for the month of October, Tourmaline is one of the zodiac gemstones for Libra and Scorpio.

Chemical Symbol:
The general symbol for Tourmaline is (Na, Ca)(Li, Mg, Al)(Al, Fe, Mn)6(BO3)3(Si6O18)(OH)4

Chemical Make-up:
Tourmaline is made up of the complex Aluminum Borosilicate element, and depending upon the color of the gemstone, one or more of a number of metal ions, usually Iron, Magnesium and Lithium.

History & Lore:
The name Tourmaline is widely accepted as being derived from the Singhalese expression tura mali, which when translated means “stone of many or mixed colors”.

Tourmaline is often referred to as the rainbow gemstone, due to the huge amount of colors that it is available in. This was certainly believed by the ancient Egyptians who believed that when Tourmaline traveled from its home in the earth's core to the surface, it did so along a rainbow, which subsequently gifted the gemstone with all of the colors of the rainbow.

Tourmalines exhibit piezoelectricity and when these stones become warm they become electrically charged – positively at one end and negatively at the other, acting like a magnet and strong enough to attract small particles of dust or ash. It is for this reason that the Dutch of old used Tourmalines to clean their pipes!

As with most gemstones, ancient civilizations credited Tourmaline gems with magical and mystical powers, including having the power to guard against danger and misfortune. Tourmalines are said to have an especially strong influence over friendship and love, lending permanence and stability to both. Tourmaline gems help to amplify psychic ability / energy and are an excellent aid to increasing self-confidence and understanding. Tourmaline is believed to help assist with tranquil sleep, calm nerves, improve concentration and creative processes and to be an aid to curing cancer.

Indicolite is believed to bring about a higher level of intuition and eloquence in communication. It is a stone of harmony, openness and tolerance.

Availability:
True Blue Tourmalines are both rare and sought after as most blue specimens will often display a shade of green.

Sources:
The majority of these rare gemstones are sourced from Northern Brazil. There are also known deposits of Indicolite in Afghanistan, Madagascar, Namibia, Nigeria, Pakistan, and Sri Lanka.

Evaluation:
Tourmaline (regardless of variety) is rated at 7 – 7.5 on the Moh's Scale of Hardness and as such is suitable for all jewelry uses and is considered durable enough to be worn everyday.

Found in an amazing variety, the sheer number of available Tourmaline colors is second to none and unmatched by any other gemstone. Tourmalines can be found in shades of blue, black, brown, colorless, green, orange, pink, red, yellow and other colors in varying shades and hues, varying from completely transparent to opaque. In addition to this there are also known occurances of bi-color, tri-color, multi-color and “Cat's Eye” Tourmalines, ensuring that the Tourmaline truly is a gemstone that is available in a color to suit all styles and tastes.

Indicolite is the rare blue variety of the Tourmaline mineral Elbaite and much like other Tourmaline varieties, it is typically eye-clean, seldom with eye visible inclusions. It's blue color generally ranges from a medium blue to deep blue. Top quality Blue Tourmaline specimens will most often be individual pieces, which are highly coveted by gem collectors and connoisseurs. The most valuable are those showing a dark and brilliant blue color that is reminiscent of a fine Sapphire or Aquamarine.

Indicolites are strongly pleochroic, meaning when the gemstone is viewed from different angles, different color intensities will be visible, with the deepest coloration always being shown along the stone's main axis. When selecting any variety of Tourmaline, go with the color that you like but generally try to steer clear of any stone that is cut too dark.

Common Cuts:
Owing to the fact that Tourmaline crystals are long and narrow in shape Tourmaline gems are most commonly, although not exclusively cut into square or rectangular stepped shapes. Most Tourmalines display a mixed color saturation throughout the gemstone which makes the cut crucial to the final look of the stone. Stones that are much too dark need to be cut so that the table will be parallel to the main axis, thus making the stone lighter in color. Lighter stones need to be cut in such a way that the table is parallel to the longitudinal axis, thus achieving a darker color.

Routine Enhancements:
Indicolites are often heat-treated in order to lighten colors and to remove “silk” (a form of natural imperfection / inclusion).

Care & Cleaning:
Use warm, soapy water and a soft brush to clean Tourmaline. Ultrasonic cleaners are generally safe. Never use chemicals such as hydrofluoric acid or ammonium fluoride to clean Tourmaline because it can erode the stone. Much like many gemstones, Tourmaline should be kept away from prolonged exposure to extremes of heat and light as this can cause permanent color change.

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