December is the lucky month with three official birthstones - turquoise, blue topaz and tanzanite, one of the newest natural gems to be discovered. According to its history, tanzanite was discovered in Tanzania in 1967 when Masai cattle herders noticed the sparkling blue gems in an area of forest that had burned after a lightning strike. As such, tanzanite has little of the long history and folklore attached to it that older gems have.
Even without the long history, though, tanzanite has made a name for itself. Its rich, deep color is seldom a pure blue - rather the crystal has undertones of rich, deep purple and lavender, giving it the color of a glowering winter sky. Its color falls on the spectrum somewhere between azure and amethyst - somehow cool and warm at the same time, and complementing any skin tone or clothing choices. Tanzanite was officially added to the American Gem Trade Association's birthstone list in October 2002, joining other blue stones to give December babies a full range of blue colors to choose from for their own birthstones.
Tanzania is the primary source of tanzanite, though there have been small deposits of the stone found in neighboring Kenya. Tanzanite is actually a form of zoisite, a brownish green crystal found in those areas. When exposed to temperatures of 600 degrees Celsius, the dull brownish crystal shifts color to the deep, rich blues and purples that have made the gemstone so popular so quickly. While the violet/blue tanzanite is the most prized and valuable, green tanzanite is also available. Among the loveliest of the tanzanite varieties is a color change tanzanite that exploits one of the stone's properties - the difference in color under different lighting conditions. Natural daylight tends to bring out the blue tones in tanzanite, while incandescent light brings out the violet. In most stones, the change is subtle, but rarely a stone shows a marked change in color under different lighting conditions, adding value rather than detracting from it.
Tanzanite rates 6-7 on the Mohs scale, relatively soft. In addition, it's a brittle stone, so setting and care are important. In earlier years, tanzanite was only available in small stones, but more sizable deposits have yielded larger stones, and flawless tanzanite is not uncommon.
Rare as a perfect summer day in December, tanzanite is an exotic newcomer that is making itself known on the world-wide gem market. It's a perfect birthstone for December babies, or to give as a gift to December brides.
Tanzanite is one of the newest gemstones currently known. It was discovered in 1967 in Tanzania, and that is still the only place where tanzanite is found. The legend surrounding its discovery says that it was first found by Masai herders returning to the grasslands after a raging fire destroyed the area.
The brilliant blue and purple gemstone has rapidly become one of the most popular gems available today. The color is unlike any other gemstone - a clear lavender blue that is cool and warm at the same time.
Tanzanite buying guide
Tanzanite is graded from AAA to B grade, with AAA being the highest quality gemstone. AAA tanzanite is a pure, clear blue-violet, with no inclusions or inclusions so slight that they're barely visible at 10x magnification. When shopping for tanzanite you may hear the term ‘Block D AAA tanzanite'. This is a reference to the divisions that have been made for mining. Much of the AAA tanzanite being mined comes from the block D area. There is nothing special about having come from Block D, but it is being used as a marketing ploy to imply that lesser grade stones are of higher value.
Most tanzanite sold has been heat treated to deepen and set the color. One of the most attractive features of tanzanite is its trichorism - its color shifting properties. Be certain to examine your tanzanite stone under different types of light. Under ordinary daylight, the stone will be more blue. Under incandescent light, the purple and red flashes of the stone will be far more evident.
Tanzanite is a relatively soft stone at 6.5 on the Mohs scale. It requires careful and respectful handling to avoid damage to the stone.
Avoid situations where your tanzanite jewelry might be scratched or knocked by other stones and surfaces. Keep the stone clean by polishing it occasionally with a soft, dry cloth and giving it a cleaning about once a month.
Cleaning your tanzanite jewelry
Clean tanzanite jewelry with warm water and dishwashing liquid. Let the piece soak for 10 to 20 minutes, then scrub with a soft toothbrush to remove any remaining residues. Avoid heat cleaners and sonic cleaners, both of which can damage the tanzanite. Dry carefully with a soft cloth before storing.
Storing tanzanite jewelry
As noted, tanzanite is easy to scratch. When storing it in a jewelry box, fold it in a protective cloth or fabric bag to prevent damage to your stone.