Tanzanite - The History of The Newest Gem

In 1967, crystals of a curious blue mineral were discovered at a remote place called the Merelani Hills, located near the east African towns of Arusha and Moshi on the foothills of Mt. Kilimanjaro in the northern part of Tanzania. It was first thought to be sapphire, but the mineral was later identified as zoisite. It is a fairly common mineral, but virtually unknown as a gemstone, and it had never been seen before in the transparent blue, violet and brownish colors such as these crystals from Merilani. Tanzanite is unusual in that it is trichroic: that is, it shows different colors when viewed from different directions. One direction is blue, another purple, and another bronze, adding subtle depths to the color. When tanzanite is found in the ground, the bronze/brownish color dominates. However, shortly after the discovery it was found that gently heating the material eliminated all colors except blue and violet. Properly oriented stones cut from these blue-treated crystals looked like the finest sapphires, only completely transparent and much larger. In daylight, tanzanite exhibits a range of hues from a light-toned violet to purple to a rich, dark-toned blue with a moderate purple secondary hue. The slightly purplish-blue color, which has been defined as the finest, will exhibit a pure blue in daylight, an environment that suppresses the purple. The secondary purple becomes visible as soon as the stone is placed in an incandescent lighting environment. Incandescent lighting will always bring out the secondary hue, be it violet or purple. Some connoisseurs prefer to see a bit of purple even in daylight. The purple adds a velvety quality to the hue. While little known by the public, there are some rare colors of tanzanite. Yellow and green colors are also available. There is also an extremely rare Chrome green tanzanite, colored blue green and appearing very similar to Columbian emerald.

In 1970 Tiffany and Co. gave the material a trade name: tanzanite, after the country of origin, which to this day remains the only known commercial source (a very small amount of tanzanite was mined in Kenya in recent years). A multimillion dollar promotion during the 1970s turned tanzanite from an "unknown" gemstone into a demand-item in jewelry stores all over the world. As a result, Tanzanite became a popular and well-known gemstone and a staple of the jewelry trade. This truly illustrates the power of promotion in creating demand for what was once a relatively unknown gemstone. The wholesale price of tanzanite reacted to these supply and demand factors in a classic way, by rising approximately 2,500% between 1970 and 1980. This track record is unmatched by any other gemstone.

During the mid 1970's, Tanzania's government turned socialistic, and the mines were nationalized. Tanzanite production officially stopped at that time. Production since that time has been sporadic, sometimes large, but often very limited. Today the demand for Tanzanite, especially in sizes between 6 and 15 carats, continues to be strong, and the supply very poor. New mining techniques at some parts of the tanzanite deposit and the liberalization of the Tanzanian economy has helped to boost production in the past few years to make tanzanite more available than ever before in the history of the gemstone. Tanzanite prices have fluctuated wildly over the past few decades, due to the changing political climate in Tanzania, but a new operator, Tanzanite One has brought stability at high prices.

Troubles in The Mining of Tanzanite

There is only one Tanzanite deposit of commercial importance, but it is very large – about 5 miles long, however only limited parts of that area have economic quantities of good gem material. It has been divided into mining lease blocks, the majority of which are controlled by a South African mining company, and the rest of the area is worked by small groups of individuals. The mining company, which goes by the name of Tanzanite One, styles itself after the De Beers diamond corporation. After taking control of the majority of  the deposit, They are now facet cutting much of the material they produce as finished goods for sale, and offering tanzanite rough only to a few selected sight holders. They also purchase the majority of the rough produced by the local small scale miners. Their near complete control has led to a reduced supply and regularly, significantly increasing prices. There is now a scarcity of tanzanite available to the public, except through the approved, Tanzanite One controlled channels. While Tanzanite One does use modern mining techniques, most of the mining done by the small operators is done using primitive and dangerous mining techniques. These small operators dig coyote holes through the mountain rocks trying to follow the deposits of Tanzanite. This has led to a variety of mining disasters, including one where more than 100 miners were killed in a flooding incident a few years back. Mining work is now done at depths up to 1000 feet below the surface. Miners often spend up to three days underground, working 24 hours per day. Many lives are also lost due to blasting accidents and suffocation. Political tensions in the mining area are unstable and do erupt into violence at times. The small-scale miners have bombed the offices of the larger mining company that operates there. Company guards from the large operator have shot at and killed some of the small-scale miners. Tensions in the area continue to this day.

As the mining in this area has gone deeper, the overall quality of the product coming onto the world market has tended to decrease and medium to lower grade materials have become more common as the best areas have become worked out. The better qualities and larger stones have become more and more difficult to obtain, and as a result, more expensive. In many cases, extraordinary fine tanzanite gemstones are almost as expensive as the sapphires of a similar color which it is used in jewelry to imitate.

Shortly after the 9/11 tragedies, some allegations were made that terrorists had a significant involvement the marketing of tanzanite. These allegations were researched and efforts were made to brand tanzanite and show that it was free from terrorist influence, but further investigation has shown that the original claims of terrorist involvement were grossly overstated and that terrorists had basically nothing to do with the actual marketing channels for tanzanite. The US State Department has also investigated this issue and publicly stated that there is no evidence that al-Qaeda or any other terrorist group is currently using tanzanite sales to finance their efforts or to launder money. In reality, the operations and controls established by Tanzanite One have virtually eliminated what little influence they may have had at one time.

 Choosing a Tanzanite

The color of tanzanite is most intense in sizes above ten carats. Tanzanites smaller than one carat are usually paler in color. Tanzanites which are more blue rather than purple tend to be more expensive because the crystals tend to form with the blue color axis oriented along the width of the crystal instead of the length. That means that if the cutter chooses to maximize the purity of the blue color, the stone cut from the rough will be smaller and will cost more per carat. The blue color, however, is so beautiful, that the sacrifice is often worth it.

Tanzanite jewelry is a little more delicate than other gemstone jewelry and should not be set in a ring that will be worn during strenuous activity. A hair softer than most gems, it is prone to scratching when worn in rings. Never clean tanzanite in an ultrasonic cleaner or resize or repair a ring set with tanzanite because the stone could shatter in the heat of a torch. The stones must be removed before any work is done on the setting. It is available in a variety of shapes and sometimes in large sizes that are perfect for an important necklace.

Many individuals have chosen to invest some significant money in Tanzanite. The increasing prices which we have seen in recent years does seem likely to continue for some time  into the future.