Tanzanite Grading
The mineral zoisite is a beautiful bluish-violet stone. When extracted from the Earth, it is known as Tanzanite. This valuable gem is only found in one location in the world, near Mount Kilimanjaro. Its symbolism includes intuition, purity, and intellect. The lovely blue color can also be associated with calmness and peace. As one of the most valuable gems, Tanzanite is often crafted into striking jewelry, such as Tanzanite earrings or even Tanzanite engagement rings. However, only the finest quality Tanzanite stones can be faceted to make fine jewelry, making grading essential.
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How is Tanzanite Graded?
Unlike diamonds, Tanzanite's price isn't strongly linked to its carat weight. Of course, larger specimens will tend to cost more, but other factors can play an important role. The cut, color, and clarity of a Tanzanite stone are instrumental to its value and price.
Tanzanite Color Considerations
Tanzanite is commonly vivid blue or rich purple. However, it can display hues of both as well as flashes of red. This is because they are pleochroic, which means viewing them in different directions causes different colors to show. The most valuable color is a rich violetish blue with hints of a pleochroic red. Regardless of its pleochroism, vivid Tanzanite is more sought after than paler gems. Additionally, blue or bluish-violet tends to be popular.
To get this color, most Tanzanite is heat treated as it is naturally brownish. Heat treating should not deter you from purchasing Tanzanite, as most gems on the market have been heated in some manner.
Tanzanite Clarity Considerations
Tanzanite can come in a variety of shapes, with the most popular being oval and cushion. Although the shape is different than the cut. The cut, including the shape and faceting of the stone, is vital to Tanzanite's color and clarity. It is especially important when considering a specimen's pleochroism. How Tanzanite is cut will determine how its color looks when viewed face-up. Gem cutters will also try to remove as many noticeable inclusions as possible without lessening the carat weight. The most valuable Tanzanite will look bluish-violet due to their excellent cut instead of violetish-blue.
Tanzanite Carat Weight Considerations
Tanzanite, like other gems, is most plentiful in smaller carat weights. Larger sizes are rare, especially considering Tanzanite can be found in only one location across the globe. Unfortunately, the smaller the stone, the less intense its color, with larger gems having a more vibrant blue hue. As with all gemstones, the larger the stone, the higher the price. However, poor quality can significantly detract from a substantial gem's value. Therefore, you should not purchase Tanzanite based on carat weight alone.
Tanzanite Grading Chart
Diamonds tend to have a standard grading chart, with grades for clarity, color, and cut. Tanzanite does not have this standardization, but most are bifurcated as follows.
- Good: This category includes pale gems that are light violet to blue in color. They may have minor inclusions that are visible to the naked eye. This is the entry-level grade for setting in fine jewelry.
- Better: These tanzanites are medium violetish-blue in hue. They tend to have very minor inclusions that can be seen without magnification.
- Best: Stones in this category account for the top 10% of available tanzanites in the world. They display a vivid violet-blue in color with high brilliance. These tanzanites are also eye-clean and free from blemishes.
- Heirloom: This category includes exclusive and top 1% of tanzanite in the world regarding quality. Rich, vivid bluish-violet color with beautiful pleochroism. Excellent brilliance and clarity.
Tanzanite Pricing
Tanzanite price isn't determined by one factor alone. As you can tell by the above grading chart, clarity and color play a significant role. Larger Tanzanite of heirloom quality will be exceptionally rare and, therefore, expensive. A smaller Tanzanite of heirloom quality may cost just as much as a large Tanzanite with a poor grade. Based on the gem's quality, prices can range from $50 per carat to more than $800 per carat.
Why Pick a Tanzanite?
Tanzanite is rarer than diamond and comes from a very limited source. These qualities make it an exceptionally good investment. Aside from its rarity, Tanzanite is also gorgeous. Its lovely bluish-violet shade is similar to a sapphire, a popular engagement ring choice. However, thanks to its pleochroism, the stone is uniquely different in that it can change colors when viewed from various directions. Those in tune with the symbolism of the stone will love that it represents clarity, calmness, and intuition.
FAQs
How to pick a good Tanzanite?
When choosing Tanzanite, look for an eye-clean stone with a vibrant bluish-violet hue.
Do Tanzanites have inclusions?
Though Tanzanite has inclusions, most can only be seen with magnification. Eye-clean stones are considered fit for jewelry.
What color is a good Tanzanite?
Tanzanite should be well saturated with a vivid bluish-violet or violetish-blue hue. Flashes of red due to its pleochroism are also sought after.
Which is a good quality grade for a Tanzanite?
Heirloom is the best grade for Tanzanite, though gems with best, better, and good grades can also be set in jewelry.