
This is a typical example of what is referred
to as a D-Block Tanzanite. The misuse of the D-Block designation is
further explained below.
 |
 |
 |
|
Purple, Pink,
Green Tanzanite |
Green Tanzanite |
Pink Tanzanite |
The three Tanzanite
examples shown above, have not been heat treated as is normal for
Tanzanite. The heating process not only changes the color to a
blue/Purple shade, but it also stabilizes the color in the stone.
Accidental exposure to heat will result in a color shift. For this
reason we do not recommend the purchase of unheated Tanzanite
gemstones.
10.76ct Medium
Bright Blue Tanzanite
Tanzanite
History
Tanzanite was first
discovered in 1967 in Tanzania, East Africa. As one of the newest and
most exotically colored gemstones, Tanzanite is part of the Zoisite
mineral species and is only found in East Africa. It is named
after the East African state of Tanzania, the only place in the world
where it has been found. On its discovery in 1967, it was
enthusiastically celebrated by the specialists as the 'gemstone of the
20th century'.
26.83ct
Intense Blue Tanzanite
The world's only known source of
tanzanite is situated in the Simanjiro district of Tanzania, In the
shadow of Mt. Kilimanjaro.
 |
 |
|
1.47ct
Blue/Purple Tanzanite Table |
1.47ct
Blue/Purple Tanzanite Culet
|
Color
Tanzanite is uniquely Trichroic, which means that in its rough form, it
radiates three different colors from each of its axes: blue, violet and
burgundy. Once cut and polished, tanzanite ranges from electric violets and pale
blues to deep royals and rich indigos.
36.89ct Tanzanite
Block D
Tanzanite: is a term commonly used in marketing Tanzanite. Block D
simply refers to the area from which material is mined. As mentioned
earlier the Tanzanite mining area has been divided into 4 blocks by
the Tanzanian government - Blocks A to D. Traditionally, larger
quantities of the best material was found in block D so the term
became synonymous with the top grade. However, it has become a
marketing ploy and is a term misused as it implies that only block D
produces the AAA grade. This is not the case - AAA comes from all
blocks, block D has traditionally just produced more of it than the
others. It is best to ignore the term based on it's misuse. It is better to use more scientific
and official grades like the GIA system than to rely on subjective
trade terms.

30.24ct Pear shaped Tanzanite
Choosing a Tanzanite
The most valuable
Tanzanite's have an intense, vivid blue color in natural light. The
best Tanzanite's
hold the brightness of their color under all different types of
lighting but due to the Trichroic nature of Tanzanite it can appear
purple blue or bluish purple. In general, a more pastel blue would be
less preferred than a vivid blue.