Tanzanite blue purple

Tanzanite is a rare blue-violet gemstone discovered in Tanzania in 1967, highly prized for its beauty and scarcity.

About this subject

Tanzanite is a blue-violet variety of the mineral zoisite, found exclusively near Mount Kilimanjaro in Tanzania. It was discovered in 1967 by Maasai herders and quickly gained prominence in the gem market due to its intense color and ability to display different shades when viewed from different angles, a phenomenon known as pleochroism. The gem can range from sapphire blue to deep violet, depending on lighting, and is often heat-treated to enhance its color.

Tanzania is the only known source of tanzanite, making it one of the rarest gemstones in the world. Mining is controlled and concentrated in an area of about 20 square kilometers. In 2002, the American Gem Trade Association added tanzanite to the list of December birthstones, replacing turquoise. The gem is prized both in fine jewelry and mineral collections, with value increasing based on color saturation and lack of inclusions.

A notable fact: tanzanite is about a thousand times rarer than diamond, and its limited supply has driven consistent price increases since its discovery. The gem has a hardness of 6.5 to 7 on the Mohs scale, making it suitable for rings and earrings with care. In 2020, the Block D Mine, a major source, was acquired by Richland Resources, which plans to expand production.

Frequently Asked Questions

Where is tanzanite found?

Tanzanite is found exclusively near Mount Kilimanjaro in Tanzania, in an area of about 20 square kilometers close to Arusha.

What is the natural color of tanzanite?

Natural tanzanite ranges from sapphire blue to deep violet, showing different shades depending on the angle (pleochroism). Most commercial gems are heat-treated to enhance the blue color.

Is tanzanite more valuable than diamond?

While tanzanite is much rarer than diamond, its per-carat value is generally lower, but fine-quality gems with intense color can reach high prices, comparable to good sapphires.