If the name didn’t give it away already, tanzanite stones are found in only one place on Earth – Tanzania, Africa. What is it that makes this locale a hotbed for sparkling blue gems? Tanzanite’s geological rarity and striking purple-blue color make them an exceedingly attractive gemstone that’s used around the world in jewelry and holistic healing.

If you don’t know much about the tanzanite stone, keep reading as we share the fine details of this special and highly sought-after gemstone.

What is Tanzanite?

Tanzanite is part of the epidote mineral group. More specifically, it is the blue and violet variety of the mineral zoisite. What makes this stone unique at a chemical level is the presence of vanadium – and probably the fact that it was all formed at the same time due to a massive shift in the Earth’s crust. If that isn’t hardcore enough, it sits on the Mohs hardness scale at 6.5, right between feldspar and quartz.

Geologists conclude that tanzanite stone formed 585 million years ago by significant tectonic activity and heat in the area that would later become Mount Kilimanjaro. Such activity, combined with the unique geological environment under Tanzania, resulted in a relatively small deposit of tanzanite crystals. Most tanzanite stone is mined at the hinge of isoclinal plate folds. Other stones formed by tectonic processes include jadeite and ruby (which is found along the plate border of the Himalayan mountain range).

Compared to other gemstones like opaland quartz, which form as a result of underground pressure and geological composition, tanzanite’s formation story is exceedingly rare. A handful of other characteristics make it even more so!

Specifications and Characteristics

Here are a few ways to identify an authentic tanzanite gemstone:

• Color: Violet blue to blue-violet to violet purple, colors can change based on the lighting and angle in which the stone is viewed from.

• Crystal structure: Zoisite (calcium aluminum hydroxyl sorosilicate) containing vanadium

• Luster: Vitreous, pearly on cleavage surfaces

• Transparency: Transparent with deep color

• Refractive index: 1.69-1.70

• Density: 3.35

• Cleavage: Perfect {010} and Imperfect {100}

Tanzanite stones are chemically composed of three primary elements: calcium, aluminum, and silicate. The complex composition makes tanzanite difficult to find even within the country of Tanzania. What is a tanzanite gemstone used for? Let’s explore how people have discovered and cherished this fine jewel.

Tanzanite Stone History

Tanzanite is relatively new to the gemstone market, especially compared to centuries-old gemstones like emeraldsand sapphires. Though it has existed for hundreds of millions of years below the Earth’s surface, tanzanite wasn’t uncovered until 1967, when a Masai tribesman stumbled upon a stone that he believed to be sapphire in northern Tanzania. A local prospector named Manuel d’Souza concluded upon further inspection that the stone was not sapphire, but a new, previously undiscovered gemstone.

Dozens of other sightings were recorded after this discovery throughout a small region of northern Tanzania. One year later, in 1968, Tiffany & Co. would lay claim as the sole distributor of the stone and shortly thereafter unveil the world’s newest gemstone: Tanzanite. Tiffany & Co. chose the name as a tribute to its country of origin.

Tiffany & Co. advertisements for tanzanite quickly went multinational. All of which marketed the fact that tanzanite could only be found in two places worldwide, “in Tanzania and Tiffany’s.” Catchy, isn’t it