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Round tanzanite gemstones featured in diamond halo stud earrings

Tanzanite Guide

A rare gemstone, tanzanite offers unparalleled beauty with its signature deep-blue hues and striking violet shades. Tanzanite has been said to possess symbolic powers that enhance cognition and dissolve stagnancy. Learn more about tanzanite’s origins, wearability and history in our tanzanite guide.

What is tanzanite?

Tanzanite is a recently discovered gemstone that comes in rich blue and lush purple hues. The color of tanzanite can change in different lighting, making this rare gemstone unique. This gem is found in only one place in the world—Tanzania—making it rarer than a diamond. Tanzanite is a birthstone for the month of December and is traditionally given as a gift on 24th wedding anniversaries.
A pear shaped tanzanite gemstone accented by diamonds in a rose gold ring
Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0
via Wikimedia Commons / Cropped from original 

Mineral: Zoisite 

Origins: Tanzania 

Symbols: Cognition 

Properties: Optimism, Intuition 

Durability: 6 to 7


Heated or infused to alter color and clarity 


Special Gemstone Care: Do not use ultrasonic cleaning and 
sudden temperature changes. 



A tanzanite gemstone in unpolished crystal form

What to Look for in Tanzanite

Tanzanite is adored for its terrific deep hues. These gems show three distinct colors—reddish purple, blue and violet—depending on what type of light they’re in. This optical phenomenon is called pleochroism. There are several aspects to consider when choosing a tanzanite gemstone.


Gemstone color is often the most important factor in determining a gemstone’s value. Blue tanzanite is rarer and more highly valued than violet or purple tanzanite, but many people prefer stones with lighter violet hues. 

An Illustration of 3 differently colored gemstones from the side


The cut of a gemstone is what gives it symmetry and shows off the stone’s color and brilliance. Because tanzanite is a pleochroic gem, the cut plays a significant part in which color takes prominence in the finished stone. 

An Illustration of a well-cut gemstone from the side


Gemstone clarity is determined by any inclusions embedded in the gem, such as gas bubbles, fractures or small crystals. Most tanzanite gemstones have inclusions that are only visible with magnification—and any eye-visible inclusions typically cause a drop in price but don’t necessarily detract from the stone’s beauty. Inclusions aren’t always a bad thing! Rarely, tanzanite contains inclusions that create cat’s eye chatoyancy, a phenomenon where light reflects off the inclusions and produces a luminescent beam, similar to that of a cat’s eye. 

An Illustration of a gemstone with very few inclusions from the side


While diamonds are sized and valued by carat weight, gemstone size is based on diameter in millimeters. The size of tanzanite influences its color—large pieces of tanzanite have the finest color, but smaller gems are more abundant. 

An illustration of a gemstone from the side with a ruler over the gem's table


Virtually all tanzanite on the market has been heat-treated to bring out the coveted blue to violet hues these gems are prized for. Heat treatments are a permanent, undetectable enhancement and don’t harm the gemstone, but rather add to its allure. 

An illustration of a gemstone being treated with oiling enhancement method


Tanzanite rates a 6 to 7 on the Mohs scale of hardness, which makes it less durable than harder gemstones like diamonds (10) or sapphires and rubies (9). Tanzanite generally isn’t suitable for intense everyday wear, such as in an engagement ring, unless you choose a protective setting, such as a bezel, channel or pavè setting.
The Moh's hardness scale showing opal at 5, emerald at 7.5, topaz at 8, ruby at 9, and diamond at 10

Choosing the Right Tanzanite Jewelry

Violet-blue tanzanite pairs handsomely with cool-toned metals like silver, white gold and platinum.

Famous Tanzania Gemstones

First unearthed in 1967 in the African country of Tanzania, Tanzanite is one of the newest additions to the colorful world of gemstones. Tiffany & Co. quickly recognized its selling potential and became its main distributor, christening the blue-violet jewels as Tanzanite to highlight the stone’s exclusive geographic origins. Tanzanite may not have the ancient history and fabled virtues of other gemstones, but it’s highly prized for its rare beauty.

How to Care for Your Tanzanite Jewelry

• Tanzanite gems are dulled by household dust, but with a simple repolish, they’re easily brought back 
   to a like-new luster. Store your tanzanite jewels in a protective cloth bag or jewelry box when you’re not    wearing them. Check often for loose or damaged stones, and protect your jewelry from harsh blows. 

• Learn more about caring for tanzanite jewelry in our gemstone cleaning guide — or let us do the dirty work for    you with our complimentary gemstone cleaning and repair on all of the jewelry we sell.

Tanzanite Buying Tips

Now that you’ve learned about this rare gem through our tanzanite gemstone education, it’s time to learn about buying tanzanite. Here are tips for choosing the perfect tanzanite stone: 

Focus on the color that matches your budget. Darker tanzanite stones will have a higher price tag than lighter ones. Both are beautiful for all types of jewelry! 
Look for a well-cut gemstone that’s symmetrical and relatively brilliant. 
Choose enhanced tanzanite stones to maximize your budget. One-time, safe tanzanite enhancements can improve the color of the gemstone. These enhancements improve the tanzanite for long-term wear. 
It’s also important to consider which metals you'll set the stone in. Tanzanite’s unique blue to purple hues are perfect in silver, platinum or white gold pieces. For even more contrast, select rose or yellow gold settings.


There’s a galaxy of extraordinary gemstones to discover and admire. Learn more about these phenomenal jewels in our gemstone guide.

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