Tanzanite is a member of the mineral family zoisite, which has been known about for nearly two centuries. Zoisite occurs in a number of varieties, the most sought after being tanzanite. This mineral family was named zoisite in 1805, some time after the Austrian scientist Baron Siegmund Zois von Edelstein (1747-1819) had identified the mineral in the Saualpe Mountains of Carintha, Austria. Siegmund Zois von Edelstein operated an iron mine in the Karawanken Mountains in Karnten Austria and encountered the mineral on his own property. Centuries later, the discovery of a bright blue transparent variety that we now know as tanzanite, created a lot of excitement in the specialist world.
A prospector named Manuel d’Souza who was looking for sapphire made discovered tanzanite in 1967 in northeastern Tanzania. D’Souza was originally from India and had been looking for stones in the wilds of Tanzania. Eventually, some natives took him to an area in the region of the Merelani Hills near Mount Kilimanjaro, around 90 kilometers from his home town of Arusha. There, he found these precious blue stones he thought were sapphire. According to legend, the Masai herders were actually the ones who originally discovered the stone, when a lightning strike set the surrounding grasslands on fire. When they returned to the land with their livestock, the blue stones were all over the ground. D’Souza soon discovered that the blue stones he had found were not sapphire, so he staked a claim with the government and began mining.
With few inclusions, by 1970, the royal blue find was soon the focus of American and European publicity. When word of the new gemstones got out, Henry Platt of Tiffany and Co. named the new gem “tanzanite” and Tiffany’s began a marketing campaign to introduce it to the public. Now, tanzanite is the pride of the gem-rich East African country, Tanzania. Soon after word of this new precious stone got out however, a murderous attack put a swift end to exploitation of the mineral. A fake car accident, in which d’Souza died, interrupted any follow up supplies. As a result, supply was unable to keep up with demand during the following two years.
Some say D’Souza’s discovery is one of the most exciting in the field of gemstones in nearly a century. Of all the new gemstones that have conquered the hearts of people in the second half of the twentieth century, none has even approximated the success of tanzanite. Within a short period of time it has succeeded in achieving worldwide popularity and major acclaim. The triggering factors for this market success are the virtues incorporated in tanzanite such as the beauty of its color, its rarity and durability, as well as its availability. Though it only rates a 6.5 on the hardness scale, its resistance to scratching and abrasion is relatively good.
Tanzanite has become one of the most popular gems in the market place. In fact, it is now the most popular gemstone after the “big four,” which consists of diamonds, rubies, sapphires and emeralds. At first, the gemstone was only available in smaller sizes, but now much bigger sizes are sold. Today, tanzanite can cost over $2000 per carat in larger sizes at retail stores. Tanzanite is far less expensive than sapphire, for which it often serves as a substitute.
Tanzanite stones are 585 million years old. There are apparently only very rare tanzanite stones that are naturally blue. Given its attractive color, rarity and the publicity, which greeted its discovery, the value of tanzanite is quite high, just a little less than that of the violet-blue sapphires it resembles. But it is rarely seen on the market and is very much a collector’s item. Tiffanys has one of the largest and most beautiful displays of tanzanite in the world. The Smithsonian Institution also has an impressive collection consisting of one faceted stone of 122.7 carats and a rare cat's eye tanzanite of 18.2 carats.
Because tanzanite was only first discovered in 1967, there is not much history, legend, or superstition about the gemstone. In Tanzania, however, women who have just given birth wear blue beads and fabric to bestow a healthy and positive life upon their newborns. This custom has been going on for generations in Tanzania.