December Birthstone - Tanzanite

Another of December’s birthstones, tanzanite, is considered the most precious of all semi-precious stones, even though it was only discovered in 1967. An estimated two million carats of tanzanite were mined before being nationalized by the Tanzania government in 1971.

The Discovery of Tanzanite

Manuel de Souza, a tailor and hobby prospector, was the first to be introduced to the stone on a trip in search of ruby deposits. Massai tribesman, Ali Juuyawatu, shared the stones with Souza who assumed the gems to be sapphires until further examination revealed a much more complex crystal structure. Shortly after discovering the stones, Souza showed them to Nairobi-based gemologist, John Saul, who sent the sample to his father, Hyman Saul, Vice President of Saks Fifth Avenue in New York. Hyman took the stones across the street to the Gemological Institute of America, where they determined the stones were a form of the mineral zoisite. This was not the first time the stone was correctly identified, that right goes to Ian McCloud, a geologist for the Tanzania government.

Tiffany and Co Introduces Tanzanite to the World

The unmatched vibrant color of the gemstone caught the eye of Henry B Platt, heir to the famous Tiffany and Co in New York, who coined the term “tanzanite” in 1968. Tiffany started a massive campaign surrounding these inclusion free stones, stating that Tanzanite could be found in two places “in Tanzania and at Tiffany’s”.

Tanzanite has continued to grow its popularity, and as of 2001, it was ranked as the second most desired colored gemstone, behind sapphire.

Local Legends Surrounding Tanzanite

After its discovery, the Maasai people began cultivating stories surrounding the origin of the stone. According to Maasai legend, a bolt of lightning sparked a fire that scorched the land. The heat from this “magic fire in the sky” is said to have transformed crystals on the ground into violet gemstones. When the herders returned to the ground with their livestock, they saw that the ground was covered in these unique stones.

In Tanzania, women who have just given birth wear tanzanite beads and blue fabric to bestow a healthy life upon their newborns.

Fun Facts about Tanzanite

• The blue of tanzanite is more evident in fluorescent light, while the violet appears more prominent in natural light.
• Tanzanite is usually reddish brown in its natural form and requires heat treating to bring out its blue/violet color. It is impossible to test heat treatment in Tanzanite, but it is assumed that all gem quality stones have been treated.
• The American Gem Trade Association named Tanzanite the official birthstone of December in 2002, the first change to their birthstone list since 1912.
• The world’s largest rough tanzanite was 16,839 carats, or 7.46 pounds, mined in 2005. It measures 22 cm x 8 cm x 7 cm.
• The famous “heart of the ocean” pendent from the hit movie, Titanic, featured a tanzanite center stone.