The popularity of Tanzanite is growing steadily. AnchorCert customers have been asking for a simple but authoritative grading standard to help the consumer understand the variation in quality and price of this rare and precious stone.

The vivid colour and excellent clarity of top quality Tanzanite is particularly evident in larger stones and it is not unusual to see a Tanzanite of several carats, often in a stunning setting, enhanced by diamonds. Tanzanite set jewellery is therefore likely to be expensive and, understandably, the consumer wants to know what they are buying and be sure it is the real thing.

Now, after months of research and investigation of other grading systems, AnchorCert Senior Gemmologist Anu Manchanda has developed a simple and straightforward grading system for Tanzanite. AnchorCert is the only Laboratory in the UK to have its own grading system for this precious Gemstone. Under the system, stones are split into one of four colour classifications depending on the intensity of colour and regardless of whether they are violet or blue. The commonly used ‘A’ system has been applied with AnchorCert grades ranging from ‘A’ for Pale to ‘AAAA’ for Vivid.

Clarity grades are in line with GIA Coloured Stone grading, ranging from IF (Internally Flawless) to I3 (Included). Marion Wilson, Marketing Director at The Birmingham Assay Office, said:“We wanted a classification system which would be easy to understand. It’s no good offering jewellers a service which adds value if it’s too complicated to explain. “People are familiar with the terminology used by GIA and it made sense to classify Tanzanite using the same terms. The AnchorCert team has done extensive work to determine exactly where the boundaries should fall. “For colour, it is the intensity which determines the rarity and value of the stone and this will be assessed against an AnchorCert set of Master Stones. The actual colour is obvious even to the inexperienced eye.”

The new service is supported by an A4 Characteristics ShowCard, which the Jeweller can display to explain the Tanzanite grading system to customers. Both loose and mounted Tanzanite stones can be graded and reports are provided on the popular credit card sized ‘Mini Report’. A mini leaflet helping to explain the AnchorCert Grading system will also accompany every item graded. AnchorCert has already signed up several well-known jewellers that deal in Tanzanite and anticipates a high demand for its Tanzanite Grading Service.

History of Tanzanite
Tanzanite was born over 500 million years ago when Mt. Kilimanjaro erupted in an area that was to become East Africa. The eruption caused a unique set of conditions to form deep within the earth - heat and pressure mixed with rare chemicals such as Vanadium to allow this exceptionally rare gem stone to form. These conditions remained constant for the entire 500 million years and Tanzanite grew.

It was first discovered by Maasai Tribesmen in 1967 when an enormous grassfire swept the land below Kilimanjaro clear. As Tanzanite is a brownish colour in its rough state, the crystals lying on the surface were never noticed. After the grassfire had burnt the land and heated the stones, they turned a bright, glittering violet-blue, making the gems sparkle in the sunlight. Today thousands of fortunate people have the privilege of wearing this beautiful gem stone but as more and more people learn about it and desire it, the more the source is mined. The top quality, deeply saturated Tanzanite gem stones (AAAA) are only 0.13% of mined Tanzanite and are becoming extremely hard to get.

Tanzanite Facts
Gem Species : Zoisite
Hardness Mohs' Scale : 6.5
Toughness : Fair
Stability to light : Stable
Birthstone : December

Caring for Tanzanite
Due to Tanzanite's relative softness, it should be treated with care. It is not a gem that should break easily but due to its relatively low score on the Mohs' Scale (6) it can scratch more easily than other gems like Ruby. To clean it do not use an ultrasonic cleaner or steam cleaner often found in jewellers. The best method is simply to use a toothbrush and warm, soapy water.