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Tanzanite Frequently Asked Questions

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. Ocean Tanzanite is traded at a lower price than pure blue-violet tanzanite gemstones. Pink Tanzanitte is exceptionally rare, and trades at very high prices. 


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 i

s ideally suited for wear in dress rings, earrings and necklaces. If you're an active person, consider jewellery that won't be exp

osed to as many bumps such as pendants or earrings.Tanzanite rates  6.5 on the Mohs scale of Hardness.  When cleaning tanzanite at the jewellery store , never allow them to clean the stone in an ultrasonic machine, which vibrates at high speeds - it its likely the stone will crack. 

What is the truth about the Tanzanite Export Ban and Buying Online ? 

Since 2011, it has been illegal for rough tanzanite over 5 grammes/ 1 ct cut to be exported from Tanzania. The ban was put in place to create much needed tax revenue, and to promote jobs and skills for the people of Tanzania .  Sadly, many companies still smuggle tanzanite out to be cut in other countries - to avoid the export tax , and thus promote the black market trade in gemstones.  Consumers should be aware of companies (often online) who falsely state that their country is part of a trade agreement which allows cutting outside of Tanzania ( shown below ) ,or tanzanite which is cut and polished outside of Tanzania.  

lapi gems

What is “D block” Tanzanite and is better than tanzanite mined in the other blocks?

The short answer is NO. 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.  This term is beloved by online sellers who wish to promote their tanzanite as superior, though it has no scientific basis and is not a guarantee of quality or value

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.                   


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. ie 2.00 carats.   

Are there synthetics or imitations?

To date, Tanzanite has not been created synthetically. The most common imitation is blue-violet glass. There was a period in the early 90's when coated tanzanite was introduced into the market, however it is not commonly found today.  Any company selling coated tanzanite is required to disclose the treatment by law. 

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. 

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.