Tanzanite is the blue-violet variety of the mineral zoisite, its unique colour caused by small amounts of vanadium. Tanzanite is only found in Tanzania, East Africa, in a miraculous strip of land only around 7km long by 2km wide. The name – after its host country – was given by Tiffany & Co who introduced it to the market in 1968 with the slogan ‘in Tanzania and Tiffany’s’, but it has gained widespread popularity ever since.
Today, tanzanite is beloved for its sumptuous, rich colouration. With remarkably strong trichroism (meaning it can show three different colours depending on the angle at which it’s viewed) it displays blue, yellow and burgundy.
Often tanzanite is heated to unveil and intensify the desired purplish-blue colour, the burgundy/brown is therefore eliminated, leaving a gemstone that appears purple when viewed in one direction and blue when viewed in another.
(In rare cases, zoisite is found in pink, green and yellow. Although some refer to these as ‘green tanzanite’, they should be correctly be called green zoisite.)
Tanzanite can be transparent to translucent, with varying colour saturation. Often found as broken fragments, but when well-formed the crystals are beautiful. Most of the crystals are a light lavender hue, but the rarest and most desirable has the stunning blue violet colour with even flashes of burgundy-red.
Tanzanite has a hardness of 6.5 on the Mohs scale, which is relatively soft. It’s therefore susceptible to scratches, abrasions and bruises. Don’t let this deter you from enjoying this stunning gemstone however. Taking these factors into consideration, tanzanite is best worn in jewellery that is either for occasional wear, for example a right-hand dress ring or set into earrings and necklaces to protect it from the possibility of being knocked or damaged. For this reason a tanzanite engagement ring would not be recommended. Avoiding ultrasonic cleaners and excess heat is also advisable.
Tanzanite’s grading scale is the same as that used for most coloured gemstones; pleasing and symmetrical cut proportions, freedom from inclusions and so on. The colour grading is more complex however, describing how saturated the gemstone is in terms of depth and intensity of colour.
A = Light (very pale)
AA = Moderate (pale)
AAA = Moderately intense (colour more apparent)
AAA+ = Intense+ (very strong colour)
AAAA = Vivid (Extremely strong colour)
AAAA+ = Vivid+ (The strongest colour it can be)
While the last three grade categories are certainly the most sought after, don’t forget that the intensity of colour must be balanced with hue – the shade of colour the gem exudes as well as evenness of colour.
Combined with superb cutting and faceting, as well as fine clarity, this is what it takes to achieve a true ‘gem-grade’ stunning gemstone which exudes life, sparkle and brilliance.
Tanzanites from The Jewel Matcher
For me there is only one trusted source of tanzanite – Tivon Fine Jewellery. My esteemed colleague Ariel Tivon has a passion for coloured gemstones, most especially tanzanites, and Tivon Fine Jewellery specialises in only the most exceptional AAA+ and above quality.
“Our personal passion for the gemstone has led us to create one of the finest collections out there, using only precision-cut gemstones combined with the very highest grades of colour.
This passion also needs the right partnership to ensure it reaches its intended destination, which is why we only work with those that hold the same passion for the collections. Helen’s and all at Ainsworth Jewellers’ love of tanzanite means they’re committed to bringing their customers the best.”