Buyer's Guide
Fine tanzanite’s strong pleochroism and intense violet-to-blue face up colors help identify the gem and provide a large part of its value. Paler colors are more commonly found and less valued. Eye visible inclusions also cause a drop in value.
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What To Look For
Due to tanzanite’s strong pleochroism, each fashioned gemstone usually displays a mix of both blue and violet hues depending on viewing angle. The majority of tanzanites mined are light to medium purple and blue colored stones. However, the gem is generally famed for the small number of intensely saturated, bluish-violet stones which usually occur in sizes above 5 carats.
Eye-visible inclusions decrease the value of tanzanite, particularly in lighter colored stones, where they’re more visible against the gem’s bodycolor. Any inclusions that might pose durability problems—such as fractures—lower tanzanite value greatly.
Tanzanite is available as fine, larger pieces with strong color or lighter material cut to standard sizes for use in mass market jewelry. Tanzanite color is less saturated in smaller sizes. Gems must be above 5-cts. in size to have deep, fine color.
Tanzanite Quality Factors: The Comprehensive Guide
Tips & Advice
1. Size and color are related.
Tanzanite usually has to be larger than five carats to reach a deep saturated violetish blue or bluish violet color. Small accent stones less than two carats in size are commonly a lighter color.
2. Consider a protective setting.
With a hardness of 6 to 7, tanzanite is softer than many gems. Exercise a little caution with tanzanite rings. A setting that surrounds the tanzanite with metal or gems will help protect it.
3. Don’t compromise on cut.
The quality of the cut can make a big difference in beauty and brilliance. Your tanzanite should sparkle in a lively way, reflecting light back evenly across the entire gem. Poorly cut gems are much less marketable and sell at a discount.
4. Work with a knowledgeable jeweler.
Because tanzanite is an unusual gem, make sure you choose a jeweler who has gemological knowledge and expertise. A jeweler who knows and loves tanzanite should have a selection to show you so you can see quality differences side by side.
Questions & Answers
Is tanzanite tough enough for rings?
Tanzanite is not as tough as ruby and sapphire, but many people love their tanzanite rings. If you are active, consider a setting that protects the stone, or choose tanzanite for a ring you don’t wear every day.
Is predominately blue tanzanite more rare than violet?
Tanzanite shows different colors from different crystal directions. Because the blue color is usually located on the short axis of the crystal, it’s often more difficult to cut a large, predominantly blue gem. Cutters have to decide whether to cut a large, predominantly violet gem or a smaller blue one. As a result, tanzanites that are blue face-up are rarer than those that are predominantly violet.
Is there such a thing as pink or green tanzanite?
In rare cases, zoisite is found in pink, green and yellow. Although some refer to these colors as tanzanite, GIA calls them zoisite.
What’s AAA-quality tanzanite?
Although individual companies might create their own quality descriptions, like AAA, AA and A, to denote the range of quality of their goods, no standard quality-grading scales exist for tanzanite.
Does GIA grade tanzanite?
GIA evaluates tanzanite but does not grade it. A GIA Colored Stone Identification Report assesses the characteristics of any polished, rough, mounted or loose material (weight, measurements, shape, cutting style and color); identifies whether it is natural or laboratory-grown; and names any detectable treatments.
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Tanzanite: Questions & AnswersCaring for Your Tanzanite
Keep your tanzanite beautiful by following simple care and cleaning guidelines.
Durability
With proper care to avoid hard blows, tanzanite can be worn in all styles of jewelry.
Care and Cleaning
Warm soapy water is always safe.
Treatment
Other than heating, tanzanite is rarely treated, but might have fractures. Only clean fracture-filled gemstones with warm, soapy water.
