Tanzanite is a rare precious gemstone variety of the mineral zoisite. Discovered in 1967 at the foothills of Mount Kilimanjaro at the site that remains its only known source in the world, tanzanite has been described as 'a geological phenomenon'. With its exquisite violet-blue hues and incomparable rarity, tanzanite has become recognised as a rare precious gemstone, competing with the likes of ruby, emerald and sapphire. As testimony to this, tanzanite was rated fourth most popular coloured gemstone in the US in 2002 and in 2003, the American Gem Trade Association named tanzanite a December birthstone, adding to a list previously unchanged since 1912. It is also estimated that Tanzanite's lifespan is no longer than another 10-15 years. This adds to its special allure and popularity as an investment stone.


Tanzanite International stocks only top quality Tanzanite and people who have seen our quality of Tanzanite, fall in love with it immediately and refuse to settle for anything of lesser quality. Each one of our Tanzanite stones are also carefully selected, graded and certified and comes with it's own certificate, which reassures the owner of its quality of colour, clarity and cut, as well as its authenticity.

Unique features of tanzanite

Rarity - Tanzanite's only known source in the world is a 5km strip of land near Mount Kilimanjaro, northern Tanzania. This single, limited source renders tanzanite at least a thousand times rarer than diamonds.

Colour- Tanzanite is uniquely trichroic, which means that in its rough form, it radiates three different colours from each of its crystallographic axes: blue, violet and burgundy. Once cut and polished, tanzanite ranges from electric violets and pale blues to deep royals and rich indigos.

African mystique - Tanzanite's exclusively African heritage and the alluring narrative of its discovery have proved to be a unique selling feature.

Relative price & investment value - Quality for quality, tanzanite is currently about a third of the price of sapphire. This, compounded by its exceptional rarity, has made tanzanite an investment stone of choice, and more likely to increase in value as supply gets less.

Tanzanite International Grading System

Colour - Tanzanite has what many would consider the finest blue hue in the world of gemstones, a color which often leaves even the finest sapphires lacking. The gem is strongly trichroic, and therefore appears to have several colours in the same stone: blue, violet and red. Good quality Tanzanite has an deep royal blue or violet colour. Colours range from rich royal blues or vibrant violet to paler watery shades, depending on whether the stone is blue or violet-dominant in colour. The colour dominance depends on whether the gem is cut and polished from the long or the short axis of the crystal shaped rough tanzanite; and the more intense the colour the better the quality.

Blue Dominant

very good

Violet Dominant

very good

Clarity - The clarity of a Tanzanite is graded in a similar manner to that of diamonds, and range between Internally Flawless (IF), and Included (I1-3). At Tanzanite International, we don't stock tanzanite with a lower clarity than VVS (Very very small inclusions). High clarity gives the stone added fire and brilliance, and significant inclusions could result the stone to crack or break, if pressure is applied.

Grading Clarity

VVS - VERY VERY SMALL INCLUSION (not visible under 6x)
VS - VERY SMALL INCLUSION (slightly visible under 6x)
SI - SLIGHT INCLUSION (clearly visible under 6x)
I - INCLUDED (clearly visible to the eye)

Cut - It is very important for a Tanzanite to be well cut, as it impacts not only on the brilliance and fire of your stone, but also on the overall quality. A badly cut tanzanite, can make the best quality look inferior, and often stones are cut to maximise weight and not beauty. At Shimansky, we stock only the best cut tanzanites, and all our tanzanites are graded for their cut as part of the certification process. As a rule, we only select fine cut stones.