sign up for latest tanzanite foundation news
Subscribe to News

Keep up-to-date with what’s happening in the world of Tanzanite by subscribing to receive our latest news via email.

Frequently Asked Questions

chameleon tanzanite

Does Tanzanite come in any other colours like green and blue?

Tanzanite is the blue violet variety of the mineral Zoisite. Rarely, Ziosite is found in other colours, (often green’s with pinks being the rarest). These colours are often called “Fancy Tanzanites” , although technically should be called 'green zoisite' rather than Tanzanite. Sometimes these stones are called “Ocean Tanzanite, Peacock or Chameleon” Tanzanite.

How durable is Tanzanite?

Tanzanite has a similar hardness to an Emerald, but is less brittle. In order to preserve its beauty, simple precautions should be taken. Tanzanite is ideally suited for wear in dress rings, earrings and necklaces. If you're an active person, consider jewellery that won't be exposed to as many bumps such as pendants or earrings.Tanzanite rates  6.5 on the Mohs scale of Hardness. 

Is all Tanzanite heated to turn blue ?

Zoisite forms redish brown - and turns into blue when subjected to relatively low heat, when it can be called Tanzanite .

However, this heating can occur naturally during tanzanite's time in the ground, so some tanzanite does come out of ground already blue.                     

 

How do I know my Tanzanite is genuine?

Look for Tanzanite Foundation’s Mark of Rarity, your assurance of rarity, quality and distinction. It is also your guarantee that the Tanzanite you are purchasing has followed the ethical route to market. 

Blue or violet Tanzanite?

This choice is a matter of personal preference. Tanzanite in all its shades continue to enchant discerning jewellery buyers seeking exceptional beauty and distinction.

What colour is the best?

Rich deep blues are the rarest, and thus command a premium. Whether you choose a pastel or richer coloured tanzanite is down to your preference and budget, but please be aware that tanzanite’s colorful brilliance intensifies in larger sizes - you’re generally not going find deeper colours in smaller sizes.

Does Tanzanite come in any other colours?

Tanzanite is the blue violet variety of the mineral Zoisite. Rarely, Ziosite is found in other colours, (often green’s with pinks being the rarest). These colours are often called “Fancy Tanzanites” , although technically should be called 'green zoisite' rather than Tanzanite. Sometimes these stones are called “Ocean Tanzanite, Peacock or Chameleon” Tanzanite.

Are there synthetics or imitations?

To date, Tanzanite has not been created synthetically. The most common imitation is blue-violet glass.

Is Tanzanite heat treated?

It should be assumed that all Tanzanite is gently heated . However, it is not " heat treated " like many other gemstones,  laboratories like the GIA cannot test for heat treatment, and there is no effect on price. Excepting stones found close to the surface in the early days of the discovery, Tanzanite is universally heat treated to produce a range of hues between bluish-violet to violetish-blue. This can occur naturally in the earth (from volcanic activity or wild fires), or through mild heating in the production process. This is considered a natural enhancement, which is permanent and stable. It is merely a continuation of what Mother Nature started. Since heat treatment is universal, it has no effect on price, and all finished gems are assumed to be heated. 

Is Tanzanite a good investment?

Tanzanite is regarded as a 'blue-chip' investment due to its rarity and value. We are living during what has become known as the 'Tanzanite Generation', where it is still possible to be a first time owner of a faceted Tanzanite gemstone. This stones ever increasing desirability and single supply area makes it one of the surest gem investments of our time.

What is “D block” Tanzanite?

Barely covering eight square miles, the Tanzanite deposit has been divided into four blocks by the Tanzanian government—Blocks A through D. Block D simply refers to the area from which material is mined. Traditionally, larger quantities of the best material were found in Block D so the term became linked with the top grade. However, fine Tanzanite comes from all blocks.

How big is the worlds largest Tanzanite?

It is a single large crystal of 16,839 carats, well over three kilograms (more than six pounds). It has been named “The Mawenzi” after Kilimanjaro’s second highest peak.

Mined by TanzaniteOne Limited, the precious stone was found 270 meters (885 feet) underground at a mine in Mirelani (in Tanzania's northern Manyara region near Mount Kilimanjaro). The famous find measured 220 x 80 x 70 millimeters (8.6 x 3 x 2.7 inches).

How big can Tanzanite be?

Tanzanites exist even in the 100+ carat range, but these are rare. Generally stones are in the below 1 - 10 carat range. Carat weight affects the price, generally as weight increases stones in the same quality bracket will cost more per carat.