Thursday, October 21, 2010

New Nigerian Red Tourmaline Find

Taken from: Gemstone Forecaster
Author: By Robert Genis

 
The Brazilian red tourmaline, Ouro Fino, was originally found in 1981. It was a killer red colour that looked like a ruby, but the goods were included to a degree similar to Colombian emeralds. Even with the inclusions, collectors coveted the gemstone. The mine was played years ago and the best stones are now sitting in collections. Many new gem dealers have never seen this stone. Red tourmaline was recently discovered in Nigeria in 1998. It came in purple, cranberry, orange/pink and multi colours. This material is long gone and most are sitting in collections or mounted in jewelry. Regretfully, none of this material was ever really red. Since the 1998 find, most of the Nigerian tourmaline material has been very low quality. The yield was low and most of the stones were cabochon quality. Last year, some very large pieces of the new red tourmaline were found in the Oyo Valley of Western Nigeria. Crystals weighing 15 and 48 pounds were found. This is unbelievable! Usually a few pieces are found here and there. The material was so large, the owners needed a tile saw to cut them. The new material is yielding about 15-20% from the rough. The great thing about it is some of the best material is bright red and at the same time clean. Until now, most red and pink tourmaline crystals were horribly included.

History
Tourmaline's name comes from the Sinhalese word "turmali," which probably means "mixed precious stones." Bright, rainbow collections of gemstone varieties were called "turmali" parcels. Sri Lankan (Ceylon) tourmaline was introduced to the European society in the late 1600s or early 1700s by Dutch traders. Similar to rubies which were later discovered to be spinels, numerous red gemstones in the Russian Crown jewels from the 17th century, once thought to be rubies, are actually tourmalines. The Empress Tzu Hsi, the last Empress of China, loved tourmaline and bought large quantities from the Himalaya Mine located near San Diego, California in the early 1900s.

Geology
Tourmaline is 7-71/2 in hardness and does not tend to chip or break. Its luster is glassy and it has a high degree of transparency. Tourmaline is a group that applies to several minerals with similar chemical compositions and atomic structures. Tourmalines belong to the hexagonal crystal systems. Tourmaline crystals begin as colourless and the red is created by trace elements.

Red/Pink colours
Corundum collectors and dealers argue over where to delineate a red ruby vs. a pink sapphire. With tourmaline, the argument is "what is rubellite vs. what is pink tourmaline?" Although the argument will continue, the new find has colours that can be broken down into four groups. The reddest colours have very dark 85-90 tones. Isn’t this always the case with many gemstones? It is almost nature’s trick. These stones are red but black out. Ideally, if you want pure red, choose the reddest stones that black out the least. Approximately 10% of the production is this colour. Generally, the best stones are red/pink with light tones. This open colour is highly desirable. Some say it is reminiscent of Burma ruby. This colour represents the majority of the material. The third colour is fuschia. This is the point in Burma rubies where the stones transition to pink sapphires. These stones have a balance of red and pink and look like pink sapphires. Finally, the last colour is a hot bubblegum pink like hot pink spinel. The last two colours represent 40%, or the balance of the material.

Sizes/Prices
The new material is available from 3mm rounds to stones of 15-20 carats. The largest stone cut so far is about 55 carats. Gemstone collection suites can presently be purchased in this new material. Relatively speaking, the new material is inexpensive. Top one carat sized stones start at $100 per carat. Prices for gem quality red tourmaline can escalate to over $500 per carat for serious large stones.

Treatments
We know today the original crystals were not irradiated or treated. The crystals are so large, they would never fit into a nuclear reactor, a particle accelerator a gamma ray facility. Ditto for heating the material. It doesn’t mean the material might not be heated in the future. However, the new Nigerian material is flying so fast out the door of the owner, they do not have time to monkey with the product.

Conclusion
Some predict the new material may be the next Ouro Fino rubellite. When those stones first hit the market, people immediately recognized the gems would be rare. The same can be said for the new red tourmaline. What makes this find interesting from a collecting standpoint is the goods are an inexpensive red stone compared to ruby and spinel. It might make sense to buy a suite of the various colours or specialize in one colour. If you always wanted to start a gemstone collection and were short on funds, this might be an excellent opportunity. Given the tight economic times, this just may be the right stone at the right time for the right price. Collectors who purchase these goods at the beginning of the market cycle might soon be sitting pretty.

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