This beautiful gemstone was discovered in 1967 in Tanzania, Africa.  The discovery was a never before seen variety of a mineral called zoisite with a brilliant violet-blue color.  To honor the discovery location, in 1969 the gem was named tanzanite by Tiffany & Co. in New York who introduced the gem to the public that same year.  The gem is extremely rare, as it so far has only been found in one location, the Merelani Hills of Tanzania below Mt. Kilimanjaro.

Tanzanite gets its mesmerizing color from an optical property called trichroic.  This means it shows different colors when viewed in different directions.  Viewed from one direction, it looks bronze.  This is the predominant color when found in the ground.  When viewed from another direction. the color looks blue.  From another direction, the gem takes on a purple hue. 

The blue colored stones are the most valuable, and the gems are gently heated by the stonecutters to intensify the richness of the hue.   Local lore has it that the effect of heat on the stone was discovered by the Masai herders noticed the beautiful blue gem crystals laying on the grass of a field where they drove their cattle.  A lightning strike the night before had started a small grass fire and the heat from the fire changed the color of some brown zoisite crystals laying on the ground among other stones.