Tanzanite Quality Scale^TM

Industry members involved in the trade of cut and polished tanzanite or tanzanite jewelry are encouraged to use the Tanzanite Foundation's grading system - the Tanzanite Quality Scale^TM. This internationally recognized system for grading and valuing tanzanite was developed in order to grow quality and price consistency, comparability and ultimately consumer and trade confidence in tanzanite.

The Tanzanite Quality Scale^TM is mutually exclusive and collectively exhaustive - each grade category is specific, and the range of grades is wide enough to ensure that the complexity and extent of variations of blue-violet and violet-blue hues are all considered.

Grading is conducted by Tanzanite Foundation licensed gemological laboratories and the Tanzanite Quality Scale^TM is available to Members and non-members of the Tanzanite Foundation worldwide.

The Tanzanite Quality Scale^TM considers the 4 C's when grading tanzanite. Generally, the higher the combination of these ratings, the more valuable the tanzanite.

• Color - Intensity of color and saturation of blue to violet
• Clarity - Description of natural flaws and inclusions
• Cut - Proportions and brilliance
• Carat - A weight management, equivalent to 1/5 of a gram

Color

Color refers to the blue in tanzanite and its degree of violet saturation. The depth of color ranges from exceptional to Pale, with a 'B' or 'V' indicating a predominance of blue or violet hues. The deeper the color, the more valuable the tanzanite. A matching pair (two tanzanites of exactly the same color) is an exceptional find and its rarity is reflected in its premium value.

Clarity

Clarity refers to any natural flaws and inclusions in a tanzanite. Tanzanite’s clarity category ranges from Eye Clean to Heavily Included. Tanzanite described as Eye Clean or Slightly Included may contain minor inclusions that can only be viewed through a jeweller's magnifying loupe, which magnifies the tanzanite by ten times. Such inclusions do not detract from the perfection of the gem to the unaided eye. Tanzanite described as Moderately Included and Heavily Included contain inclusions that can be seen with the unaided eye. The more flawless the tanzanite, the more valuable it is.

Cut

Cut refers to the proportion and brilliance of a tanzanite. A very good cut ensures that the stone’s facets reflect light to create maximum brilliance. If tanzanite is cut too deep or too shallow, its radiance will deflect through the sides from the bottom of the stone, detracting from its brilliance. The more precise the craftsman’s cutting, the more valuable the tanzanite.

Carat

Carat is the term used to measure a tanzanite’s weight. One carat is 100 points and weighs 1/5 of a gram. Two seemingly identical tanzanites will have different carat weights if they vary in depth.

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