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Blue + Purple Variety | Tanzanite

Tanzanite has the ability to express blues and purples in a deeply saturated and seemingly mysterious manner much their own. With fine examples known to make blue and purple sapphire and dim by comparison, tanzanite quickly rose as a stone of importance after its discovery in 1967. A variety of the mineral and gemstone zoisite, tanzanite's fame has spread far and wide to create recognition globally. With its trichroic properties, tanzanite can display three different body colors when viewed from varied directions. Blue, purple, and an unsaturated, bronze hue can usually be seen in tanzanite with a keen, naked eye.


Tanzanite's celebrated blues, indigos, and purples are revealed when zoisite's vanadium trace element reaches specific levels of valency within its crystal structure (Ca2Al3(SiO4)3(OH)). To carry the name “tanzanite”, each gem's cool hue is gained from the application of heat, typically by means of treatment. Natural zoisite's common brownish hues are removed with simple heat in order to give way to a consistent blue, allowing cutters to choose the most beautiful color from each crystal. Stones of smaller size are appreciated for their soft, lavender tones, while gems that reach bigger proportions can gain the striking qualities of saturation. Pure blue tanzanites are held as prized, as their cutting leads to an increase in loss of rough material.


Ranging from a 6 to 7 on the Mohs scale of mineral hardness, tanzanite requires delicacy and is best for use in earrings and pendants rather than in jewelry that will see heavy wear. December babies chose tanzanite as their alternative birthstone in 2002, while its recent discovery leaves it unaffiliated to the zodiac. The stone is said to have a positive effect for the modern human, bringing a sense of calm and clairvoyance to the hectic, overworked life of the wearer. Tanzanite has found use in meditation, as it is said to help increase spiritual awareness on all levels. 


Hardness :


RI :

1.691 to 1.700

SG :


Gem DNA :


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