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Tanzanite Gemstone

What is Tanzanite?

One of the rarest and most beautiful gemstones on the planet.

In the light of day, deep electric blues evoke that ‘love at first sight’ feeling, and then by the evening its purples, violets and reds ignite a sense of passion. A gemological and geographical phenomenon.

Found in only one location in the world Tanzanite is truly spectacular! Claimed to be 1000 times rarer than Diamonds, Tanzanite is the blue variety of Zoisite, found in Tanzania, Africa. Even though Zoisite occurs widely, the geological conditions that are required to enable the gem to turn into its trademark blue are so rare that it has been described as ‘more astounding than the stone itself’.

Tanzanite is extremely popular due to its trichroic nature, which means that three different colours can be seen when looking at the gem from different angles. In Tanzanite’s case these colours are blue, pinkish violet and pink.

As with many gemstones, the darker, more vivid its colour the more valuable it is; and dark blue Tanzanite is currently amongst the most desired, and therefore most expensive gemstones in the world. So enchanted is anyone who sees this gemstone that today it is often talked about with the same reverence as Diamonds.

Hailed as the gemstone of the 20th century, it has been recommended to wear Tanzanite as an anti-depressant, due to the nurturing, emotionally supportive and cheering energies it is said to bestow. The huge demand for this gemstone led to the Gemological Institution of America adding the gem to the official birthstone list in 2002, for the month of December.



There are several different theories about who discovered Tanzanite and when. The version we believe is that it was discovered by Manuel de Souza, who was an Indian tailor who travelled the world prospecting for gold and gemstones. Affectionately known as ‘Mad Manuel’, he mended clothes to pay his way across Africa, usually on foot and unarmed, seeking gold and diamonds in the remotest of places.  In the summer of 1967, Manuel was living in Arusha in northern Tanzania, and selected an area to explore one weekend. He hired a driver and set off.  However, the roads were so bad that his driver refused to continue any further than the village of Mtakuja – Manuel and his equipment were dropped off, so Manuel decided to explore that area instead. At around noon on July the 7th 1967, Manuel de Souza, in the shadow of Mount Kilimanjaro, was suddenly captivated by a transparent blue stone sitting on the ground glinting in the Tanzanian sun.

Taking it home, he realized it was too soft to be a Sapphire, and decided the closest thing in his gem reference book was Olivine. He registered a claim with the Tanzanian Government on July 25th 1967 to extract Olivine, which was later amended to Zoisite on April 17th 1968. Soon after registering his first claim, he returned with a small team and began a small-scale operation.

John Saul’s father Hyman Saul took the gem to Henry B Platt (the great grandson of Louis C Tiffany) and Tiffany’s president, Walter Hoving. They were completely awestruck by the beauty of the gemstone, a gem which he later named Tanzanite, after the country where it was discovered, and this amazing gemstone was launched, with great fanfare, at Tiffany’s in 1969.





Intense geological research has shown Tanzanite's geology to be totally unique. The chance of it occurring outside the current production area (and its immediate vicinity) is less than a million to one.

So Tanzanite is rare in both a gemological and geographic sense.

In fact, its single source and limited supply makes it at least one thousand times rarer than a diamond.'


Bi-Colour Tanzanite

Fancy coloured Tanzanite make up less than 10% of all Tanzanite mined. This means that Bi-Coloured Tanzanite is around 10,000 times rarer than a diamond.

Technically known as 'Fancy Zoisite' by gemologists, trade names include 'Bi-Coloured', 'Chameleon', 'Peacock', or 'Ocean' Tanzanite. The most common colours are similar to a peacock feather – a mixture of blues, greens, and purples.

These stones are coloured the way they are due to a rare difference in chemical composition – it is not linked to the heat treatment. They have more chromium and less vanadium than the majority of Tanzanite. It is possible to find pieces that show a clear distinction between a greener form of Tanzanite and the blue form within one gemstone as a 'split' – but these are exceptionally rare.

The Tanzanite which tend to command the highest prices of all are those which display yellow, champagne, or pink colours. These are the rarest of all, and are the most highly prized.

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A vivid and very rare Tanzanite.