Pleochroism complicates the cutting process of tanzanite but also presents opportunity. The color of a finished stone will vary depending upon how the table of the stone intersects the crystallographic axes within the rough. The top color for tanzanite is a vivid blue. Cutters must examine each piece of rough and determine if they can cut it in an orientation that will yield a finished stone with maximum face-up blue color. If that is possible, they then determine if changing the orientation of the cut will yield a larger stone of second-quality color that will sell for a higher price.
Deciding how to cut tanzanite is an exercise in skill, knowledge, and price estimation. In the cutting of tanzanite, some of the most highly skilled employees examine the rough and plan how it will be cut to maximize color or value. The stone is then cut into a preliminary shape - known as a preform. That is the step where value is gained or lost. It must be done carefully and with a high level of skill for every important stone.
Tanzanite gem: A violet-blue tanzanite measuring 7 x 5 x 3 millimeters in size and weighing 1. This grade of tanzanite is often seen in mall and chain store jewelry.
The stone in the photo at the top of this page might be seen in exclusive jewelry stores or in showings of designer or custom jewelry items. Tanzanite is like all other gems in that small stones are more abundant than larger stones. Most faceted tanzanites are under five carats in weight. Stones over fifty carats are very rare. Small stones are typically cut into calibrated sizes for use in commercial jewelry.
Those with top-grade color are the most valuable and often go into custom or designer jewelry. Large stones with exceptional color are very rare. These are often purchased by collectors, museums, or investors. Some are also used to make special pieces of custom or designer jewelry. The size of a tanzanite gem influences its color. If you have two stones of equal saturation, the larger stone will have a richer apparent color - because the distance that light travels through the stone has an influence on its perceived color.
Tanzanite is a beautiful gem. In addition to its beauty, it has some properties that require it to be given special care. Tanzanite is best suited for earrings, pendants, and other jewelry items that will not encounter abrasion and impact. It is less suited for use in a ring. Many jewelers recommend that "tanzanite rings are for dress rather than daily wear. Hardness is the resistance of a gem to being scratched.
Tanzanite has a hardness of about 6. This hardness is low enough that the gem is vulnerable to being scratched during normal wear if it is used in a ring. This problem can be reduced if the setting is designed to protect the stone from impact and abrasion, or if the ring is not worn during activities when the chance of impact or abrasion is high.
Toughness is the resistance of a gem to breakage. Tanzanite has one direction of perfect cleavage that could result in the gem being chipped or broken if it receives a sharp impact.
Again, settings can be designed to protect the stone, and the owner can avoid wearing the piece during certain activities to reduce the probability of damage. Tanzanite is also sensitive to sudden temperature change and is more subject to breakage at that time. Color stability in tanzanite is good. Heat-treated stones hold their color and are unlikely to fade under the normal light exposure and in the temperature range of the human environment.
As with all gems, contact with acids and other chemicals should be avoided because the stone might be etched or damaged. If cleaning is needed, warm water and a mild soap are recommended. Steam and ultrasonic cleaning are not recommended. Tanzanite map: This map shows the location in northern Tanzania where all of the world's known commercial tanzanite production occurs.
In , when the first tanzanite had been faceted and prepared for the market, jewelers and the public knew nothing of the gem. They had never seen its blue color or heard its name. To introduce the world to tanzanite, Tiffany and Company launched a public education program.
Tiffany prepared educational materials that would make consumers aware of the gem, and they prepared materials to help jewelers understand it, market it, and explain its characteristics to their customers. When a new, previously unknown gemstone enters the market, every person who sells and buys must be educated before transactions can occur. More recently, in , TanzaniteOne Mining Ltd, the leading miner of tanzanite, and a company that cuts, manufactures, wholesales and retails tanzanite gems and jewelry, established The Tanzanite Foundation , a non-profit organization that promotes tanzanite.
The Foundation prepares educational materials for retailers and consumers, assists with retail staff training, and assists retailers with tanzanite promotion. The Foundation is also a participant in the Tucson Tanzanite Protocol , an organization that works to ensure that tanzanite has an ethical route to market, similar to how the Kimberly Process works to prevent conflict diamonds from entering the diamond market.
The price history of tanzanite has seen many sharp rises and falls. Decisions and regulations of the Tanzanian government can have an immediate impact on the availability and price of the entire world's supply.
Tanzanite does not have the price insulation enjoyed by gems that are mined in multiple countries and on different continents. Events such as floods or mining challenges also have an immediate impact upon supply and price. Illegal mining and smuggling have also moved the price of tanzanite. In and large numbers of illegal miners entered the tanzanite mining areas and began to aggressively mine the easy-to-access areas.
This occurred at a height of tanzanite prices. They then dumped a flood of illegal production into the market, causing a sharp decline in tanzanite prices during the following two years. When prices change, commercial-grade gems usually experience the greatest price instability. These are the most abundant grades of tanzanite where price competition is highest. Top-quality stones, especially those in larger sizes, are very rare. As a general rule, they tend to retain their value in down markets and increase in value in rising markets.
Tanzanite before heating: Tanzanite in the rough state, before heat treatment. Note that the colors are brownish and unlike the vivid blues that are seen in finished jewelry.
Inexperienced people in the field might not notice this material. Photo courtesy of The Rare Gemstone Company. Heat-treated tanzanite: Tanzanite after heat treatment at degrees centigrade. Note how the color has changed to a vivid blue. Heat treatment is done to almost all of the tanzanite on the market today. With the exception of a small amount of naturally blue material, heating is the source of tanzanite's desirable blue color.
This treatment is widely known and should be expected by retailers and customers. A small amount of untreated tanzanite with an excellent color is found in the mines.
This naturally blue material is preferred by some buyers. An article on The Rare Gemstone Company's website has good photos of tanzanite before and after treatment and explains why the color change occurs.
Synthetic tanzanite is not known in the marketplace. When this article was last updated in late , a literature review did not indicate that anyone had successfully produced and marketed synthetic tanzanite. However, stones are being offered for sale as "synthetic tanzanite". It normally comes out of the ground a brownish-red color. Another difference between the two stones is that Sapphire is harder than Tanzanite.
While both can be worn in pendants, earrings and rings, Sapphire is naturally harder than Tanzanite. The value of tanzanite is based on the 4 c's just like a diamond. Deeper colors have more value. Most tanzanites are quite clean and visible inclusions affect the value dramatically. Price per carat jumps at 1. Price per carat peaks at 3. Tanzanite is available in blue, purple or violet-blue.
The most sought after color are intense blues. Any colors outside this range are less valuable and not as rare and the deep colored purple and blue Tanzanite gemstones.
Unheated Tanzanite is brown in color and doesn't get it's blue and purple colors until it is heat treated. Buyers often confuse Tanzanite with Sapphire or Amethyst due to the color. During Steve Moriarty's last trip to Tanzania learn more here in November of , he purchased many pieces of rough Tanzanite, which is sometimes called 'raw' Tanzanite.
This is when Tanzanite has not yet been cut yet and has just been found in the mines. Because there is a limit to how much and how big of a rough Tanzanite gemstone you can bring back from Tanzania, much of the rough Steve Moriarty cut there in Tanzania. Some of the dealers he met allowed him to use their cutting machines in their shop to cut and polish the raw stones allowing him to bring back more to the United States than he would be able to in their previous form. It's also cheaper to buy these stones in the rough than cut.
This is because you then have to pay for the labor to cut them. Most of the Tanzanite you see in shops has been delivered to those shops already cut and polished. Here at Tanzanite Jewelry Designs, we not only have the finished gemstones, but also a ton of raw gemstones because Steve Moriarty enjoys cutting them in our retail store in Crown Point, IN.
If you are ever interested in seeing Tanzanite in the raw form, please stop by our shop and Steve would love to show you what your Tanzanite looks like before it's all cut and polished and ready to be worn.
In this video, Steve Moriarty talks about how to grade Tanzanite gemstones. Steve takes the extra steps when grading Tanzanite to make sure you are getting the best stone and the proper grade. During Steve Moriarty's recent trip in November of to Tanzania in search of Tanzanite, we decided to record much of what went on when we were there.
The video below will help show you just what is all involved in the whole process and finding and buying Tanzanite throughout Tanzania including Arusha. It's not as easy as one would think. You can just stop off at the neighborhood Tanzanite Shop and pick up some loose Tanzanite.
The video is about 7 minutes long, but really gives you an in-depth look at the entire interesting process. During Steve's recent trip to Tanzania, Africa in search of Tanzanite, they traveled into the mines looking for Tanzanite much of the time. In the video below you are going to see what's it like to travel 1,ft down into a small hole in the ground, known as the Tanzanite mine.
Before going in, Steve, Matt and Sune will break down what to expect when you get to the mines, you can see the difficulty of just getting to the mines and why it's something you might not want to do yourself.
Steve has been traveling to Tanzania for over 12 years and has made many contacts with dealers and guides there, which is why he is so comfortable during the whole situation. It could be definitely a stressful situation for anyone coming to Tanzania for the first time, traveling to a mine for the first time and especially for those that may be afraid of being in confined places!
Now unlike a lot of sites out there, we are not trying to pass off a poor-colored Tanzanite and call it Lavender Pink. This came out of the mine this way and was personally cut by Steve. The color of this Tanzanite is spectacular and is unlike anything he has ever seen. He does say the color reminds him of kunzite, which you can learn more about here. As I mentioned before, Steve has never seen this color before. And with the shortage of Tanzanite read about that here , this makes this color even more rare.
This is why the high price for this stone. You will probably never see another one like it and no one will ever be able to purchase it This stone specifically is over 2 carats and in a pear shape. We are working with friends in Tanzania to look for more of this gemstone. We have connections with some of the best local dealers in and around Arusha, Tanzanite. They will be informing us if any more Tanzanite of this color is found.
If so, we will be the first to snap it up, but I wouldn't hold your breath for it. You could be waiting a long time. Like the rare colors of Tanzanite. You can see the complete collection here. In the video here Steve Moriarty is going to show you how to enhance natural Tanzanite with heat. Most people don't know what the real color of Tanzanite looks like before the heating process. It's amazing that heat can change a stone this much, but it's really a common process in the jewelry industry.
How rare is tanzanite? Relative to other gems tanzanite has a high rarity level. The supply is sufficient to satisfy current demand but when we consider the short time it has been available, about 45 years, the amount sold in the world is small compared to most gems which have been mines for hundreds and even thousands of years.
Projections of the future of mining production is at most 25 years so relative rarity over time is extreme. About 25 years ago Tanzanite was very hard to get and very rare. And in the next 25 years Tanzanite will once again not be mined and it may go out of existance. It's only been mined since and only in Tanzania This is a misconception from when tanzanite was first found. Sapphire was blue so the idea was that the blue was more like sapphire so it was more valuable to be blue.
But fortunately most prefer the blue violet as most tanzanites are blue violet. The blue violet stones are actually more beautiful in both daylight and incandescent lighting. The blue stones are usually not very attractive in incandescent lights. When tanzanite was first discovered it was looked on as an alternative to sapphire and the predominantly blue stones were considered more valuable. After a while the public started to look at the gem for it's own unique qualities and found beauty in all of the unique color variation available in tanzanite.
Only a small percentage of tanzanite have a sapphire like color in all lights including incandescent so it is fortunate that this color is not the most desired.
We have come to appreciate the color changing ability of this gem as we do with a fine alexandrite. I appreciate the lovely blue color we see when tanzanite is viewed in daylight and I get great pleasure when the blue turns to a mixed blue violet and on occasion to pure violet. Both the pure blues and those that change in daylight to incandescent lighting from blue to violet are highly desirable but the color changing gems are the ones that have endeared this gem to the novice and the aficionado of fine and rare gems.
Tanzanite can be identified by the Gemological Institute of America. They will only identify if it is tanzanite. They do not provide any grading of the quality of the stone only weight, measurements and whether it is tanzanite or not.
We will be glad to provide this service at the additional charge. Turnaround is approximately two weeks. What is the hardness and durability of tanzanite? Tanzanite is 6. It's general durability is comparable to amethyst, citrine, garnet and tourmaline. Exceptional Quality. Birthstone Jewelry. Create Your Own Keepsake.
Tanzanite Engagement Rings. Tanzanite Rings. Tanzanite Earrings and Pendants. Tanzanite Meaning, Powers and History The Meaning and History of Tanzanite Tanzanite is a member of the mineral family zoisite, which has been known about for nearly two centuries. Zoisite occurs in a number of varieties, the most sought after being tanzanite. This mineral family was named zoisite in , some time after the Austrian scientist Baron Siegmund Zois von Edelstein had identified the mineral in the Saualpe Mountains of Carintha, Austria.
Siegmund Zois von Edelstein operated an iron mine in the Karawanken Mountains in Karnten Austria and encountered the mineral on his own property. Centuries later, the discovery of a bright blue transparent variety that we now know as tanzanite, created a lot of excitement in the specialist world. Eventually, some natives took him to an area in the region of the Merelani Hills near Mount Kilimanjaro, around 90 kilometers from his home town of Arusha. There, he found these precious blue stones he thought were sapphire.
According to legend, the Masai herders were actually the ones who originally discovered the stone, when a lightning strike set the surrounding grasslands on fire. When they returned to the land with their livestock, the blue stones were all over the ground. Design Your Own Family Keepsake Combine Tanzanite with any gemstone to create your own unique family keepsake with the birthstones of your loved ones, or your favorite combination of colors. Select a gold color:.
With few inclusions, by , the royal blue find was soon the focus of American and European publicity. When word of the new gemstones got out, Henry Platt of Tiffany and Co. Now, tanzanite is the pride of the gem-rich East African country , Tanzania. Soon after word of this new precious stone got out however, a murderous attack put a swift end to exploitation of the mineral.
As a result, supply was unable to keep up with demand during the following two years. Of all the new gemstones that have conquered the hearts of people in the second half of the twentieth century, none has even approximated the success of tanzanite. Within a short period of time it has succeeded in achieving worldwide popularity and major acclaim. The triggering factors for this market success are the virtues incorporated in tanzanite such as the beauty of its color, its rarity and durability, as well as its availability.
Though it only rates a 6. Tanzanite has become one of the most popular gems in the market place. At first, the gemstone was only available in smaller sizes, but now much bigger sizes are sold. Tanzanite is far less expensive than sapphire , for which it often serves as a substitute.
Tanzanite stones are million years old. There are apparently only very rare tanzanite stones that are naturally blue. Given its attractive color, rarity and the publicity, which greeted its discovery, the value of tanzanite is quite high, just a little less than that of the violet-blue sapphires it resembles. Tiffany 's has one of the largest and most beautiful displays of tanzanite in the world.
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