Blue with violet modifier
Care must be taken. Tanzanite
Meralani district of Tanzania
challenges, flooding, hand mining limitations, and tremendous
popularity have now created a worldwide shortage of
tanzanite. The finest material tends to be older stock,
which is currently sold at a premium.
is a variety of zoisite, discovered in the Merelani district
of Tanzania, near Mount Kilimanjaro in 1967. So far, all
tanzanite discovery has been limited to a six kilometer
strip in this area, which was divided into four blocks,
labeled A, B, C and D. Block C is the only site still commercially
producing rough tanzanite at this time.
purple and blue varieties of the stone are the result of
heat treatment. The stone is a yellowish-brown "bug
juice" color when it is mined, but when heated to between
800-900 degrees Fahrenheit, it becomes that gorgeous violet
blue that is used in jewelry. The stone has never been found
in another locality, so it is indeed a depleting resource.
It is somewhat soft (6-7 on Moh's scale of hardness), and
has a direction of cleavage, along which it can be easily
broken. It is desirable because of its' elegant and opulent