Tanzanite

Tanzanite is a blue to violet gemstone which is a member of the zoisitemineral group. It was discovered in 1967 in the hills of Northern Tanzania, which remains the sole source of tanzanite to this day. Exactly who made the discovery of tanzanite is the subject of some debate. According to some, the first tanzanite crystals were found by Masai tribesman, Ali Juuyawatu. Other reports state that the discoverer was Ndugu Jumanne Ngoma. Finally, a further account credits Manual de Souza with the discovery of tanzanite on July 7, 1967. Tanzanite was given its name by Tiffany & Co. who promoted the gemstone, resulting in its sudden popularity.

Tanzanite is pleochroic, which means that it shows different colors depending on the viewing angle. In order to get the preferred blue or violet-blue hue, gem cutters must properly orient tanzanite gemstones. The vivid blue of tanzanite can rival fine sapphire and makes tanzanite an extremely desirable gemstone. This attractive color is so sought after that tanzanite is routinely heated to enhance fine blue and violet hues and minimize the less desirable brownish tones.

Tanzanite Color

Tanzanite ranges in color from ultramarine to sapphire blue. Under artificial light, it may appear more violet. Tanzanite’s pleochroism means that it can appear blue or violet when viewed from different angles. Tanzanite has a higher color saturation in gemstones of over 5 carats. The most desirable color for tanzanite gemstones is a deep saturated blue or violet-blue.

Tanzanite Clarity and Luster

When buying tanzanite gemstones, an eye clean stone should be sought. Tanzanite has an attractive vitreous luster. Eye-visible inclusions decrease the value of tanzanite, except in the very rare cat’s eye tanzanite, which has desirable inclusions that cause chatoyancy (the cat’s eye effect).

Tanzanite Cut and Shape

Tanzanite is mostly faceted in both traditional and fancy shapes and a variety of cutting styles. When cutting tanzanite, lapidarists generally take cost into consideration, which means that tanzanite is often cut into ovals and cushions. The gemstone’s main color depends on the orientation of the cut. Extremely rare cat’s eye tanzanite is cut en cabochon to display the desired chatoyancy.

Famous Tanzanite Gemstones

Probably the most noteworthy tanzanite gemstone is the “Queen of Kilimanjaro”, which is set into a white gold tiara along with 803 garnets and 913 diamonds. It is thought to be one of the world’s largest faceted tanzanite gemstones, and weighs 242 carats.

In the Smithsonian Natural Museum of Natural History collection there is a 122.70 carat tanzanite gemstone. Also in the Smithsonian collection is a Schneider tanzanite ring, which features a 12.11 carat tanzanite gemstone, and a Petersen tanzanite brooch with a pair of matching tanzanite gemstones, weighing a total of 30 carats.

Tanzanite has been worn by many Hollywood stars such as Cate Blanchett, who wore a Chopard tanzanite necklace to the Cannes Film Festival. Penelope Cruz’s engagement ring has a tanzanite central stone and Anne Hathaway wore tanzanite drop earrings to complement her electric blue Armani dress during the 2011 Oscars.

Source: Gem Select