Saturday, January 23, 2010

Daimond Tanzanite

Daimond Tanzanite


Tanzanite was unknown till 1967. It was discovered on the slopes of Kilimanjaro at the foot of the Merelani Hills, Tanzania – the only place in the world to mine Tanzanite.
Tanzanite is the name of the blue variety of the mineral Zoisite and it is believed to be 600 million years old.




COLOUR GRADING
Tanzanite can show a dominance of intensity of either Blue or Violet or a combination thereof. When colour grading the dominant colour (HUE) of the stone will be mentioned last e.g. Blue-Violet (Violet being the dominant colour) and Violet-Blue (Blue being the dominant colour).


There are five categories of saturation (the strength of the hue). Vivid being the darkest colour on the grading scale and pale being the lightest.








Each stone is carefully graded against the Grading Master Set to achieve the correct colour grade.





CLARITY




Clarity - Refers to the imperfections that may occur in the stone.
LC: Loupe Clean - No internal inclusions visible using 10x magnification. The stone may have small abrasions that are invisible to the naked eye.
EC: Eye Clean - Minor internal inclusions and external abrasions not visible to the naked eye.
LI: Lightly Included - Minor noticeable inclusions that can be seen with the naked eye.
MI: Moderately Included - Larger noticeable inclusions that can be easily seen with the naked eye and have a negative affect on appearance.
HI: Heavily Included - Inclusions that cover majority of stone and have a serious affect on appearance.
TANZANITE CERTIFICATE
We will provide full Certificate for stones bigger than 0.50ct.








 

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