Giant 720+ carat kunzite cut by John Ramsey and featured in Gems and Gemology. Ramseygems.com
A long time ago we were offered the opportunity to purchase the large kunzite crystal shown in the photo at the very top of this post. It weighed in at about 1 kilo which equals about 5,000 carats. After days of thinking and figuring we sawed the gem as you can see in the second photo. In photo #2 the sawed pieces are sitting on the saw itself. It was a nervous time but we were lucky and the sawing came out just fine.
In the third photo you can see the sawed pieces, one finished piece, and one preformed piece attached to the “dop” which fits into the faceting machine. Finally in the fourth photo you will see the largest finished piece which came out at about 720+ carats.
The largest two pieces wound up being sold to a gem dealer one of which he told me would wind up in his personal collection.
The third largest piece wound up in the collection of a university on the East Coast. The 230 carat “baby” of the group wound up with a gem dealer.
Large Rhodolite garnets are notable for their nice color despite their large size. Many gems have better color with more size but red garnets can be an exception. This beautiful specimen is over 40 carats and is just beautiful. Other red garnets such as pyrope and almandine tend to make beautiful stones in the one-carat size and get much too dark as they get bigger. Rhodolite was originally discovered in North Carolina and according to legend named after the rhododendron flower. Rhodolite is generally now found in Tanzania as its most prolific source. Through the years we’ve had a few spectacular large Rhodolite gems many from Tanzania and a few from Sri Lanka.
Alexandrite is known as the color-changing gem. In the case of the Alexandrite from Nova Era Brazil the change is most often the change from the color of an Indicolite tourmaline to the color of an amethyst. In both cases the colors are attractive. Other mining locations produce color changes that are different than Nova Era. For instance years ago when traveling to Sri Lanka we saw a few pieces of very expensive Alexandrite that went from muddy brown (with a little rusty orange) to muddy green (emphasis on muddy). The change was not startling but the colors were unattractive. About 16 years ago (or so) there was a discovery of Alexandrite in India. The colors in that case are nice to look at and resemble (to a certain degree) the colors of Morganite which are: kind of peachy to kind of pink (both phases are accompanied by a little, very little tan). The Indian stones are attractive and the color change is noticeable.
One interesting thing about the color change of Alexandrite is that most films and most cameras are partially color blind to the color-change. We ran across this issue when we wrote our first book. That was back before digital cameras and we had a devil of a time getting the color at all right. We went from Kodachrome to Ektachrome to Fuji and it was all a bust. Even now the digital cameras will tend to only see the blue or green phase and not see the other. Interesting to know how much more sensitive our eyes are in comparison to cameras and films.
Alexandrite is a color variety of the mineral Chrysoberyl. Chrysoberyl is the third hardest of the commonly known gems. Chrysoberyl is a crystalline form of Beryllium-Aluminate. As you may recall Sapphire and Ruby are collectively known as corundum. Corundum is the second hardest of the commonly known gems. Corundum is pure aluminum oxide. The second and third hardest gems both have aluminum as a major ingredient. Interesting!!!
Aquamarine is an elusive gem. On a worldwide basis there are people mining for aquamarine all the time. Much labor and capital is expended to find this elusive gem. If the public knew just how difficult it is to find aquamarine and bring it to market there would be a run on the aqua market and make it even more expensive and hard to obtain. There is an old saying that for there to be a market for strawberries everybody has to taste at least one berry. Aqua is in such short supply that even March babies only infrequently own their birthstone. We at Gems At Large have been successful in bringing lots of aqua to our USA customers at better prices than they have seen before. Enjoy the photo of this pair of 9mm aquas—unusual this large in round stones. All our best
As gems have become more widely known around the world spinel has become one of the beneficiaries. Always appreciated by gem connoisseurs, spinel has been gaining ground in popularity. If there had been large finds of spinel all through the years perhaps it would have been better known. But spinel is rare. How rare? That is always difficult to measure in a fragmented world market. One measure however is that large gems like our pictured stone cost thousands of dollars per-carat. This particular specimen is over 12 carats in weight. Other more widely available gems are still available for $20.00 per-carat or even less. That is probably the best measure of spinel’s rarity. It is difficult to find in the market—in large sizes, when you want it, in the cut you want and so forth—it is in better colors and larger sizes—unobtainium.
*The word “unobtainium” has been around for a few decades. One theory as to the origin of the term has it being invented by aerospace engineers as a material they would like to use but can’t find or afford in the creation of aero planes.
Last post everybody loved the picture of the rough-uncut Morganite crystal. We decided to add in another photo of rough Morganite. This time you can see the more normal orange color that a lot of Morganite displays coming out of the ground. From certain mines the color is intense enough that cut stones show a nice color as-is. Some people like the peachy color. If you take these stones and put them out in the sun—especially a hot Brazilian sun—they will turn pink. Many people like the pink color. The pink color is stable and will not turn a different color in the sun. If a person wants to accelerate the color change from Peach to Pink all you have to do is put the stones in a kiln. Run the kiln up to about 900` and turn it off. This simply accelerates a natural process and is accepted and well known in the gem trade.
A number of our established clients know about spinel. Spinel is a relatively unknown gem. It has been unknown at least partly because it is very rare. It is chemically related to corundum (ruby/sapphire) in that spinel and corundum both have aluminum as a major component. In corundum is largely aluminum while spinel has both magnesium and aluminum in it. Due to its rarity spinel can be quite expensive. Due to a lot of writing about spinel in the last 10 years people’s awareness of spinel is greater than ever driving up spinel prices even more. Even back in the 1980’s large red spinels could reach prices in the thousands of dollars per-carat. One example of that is the gem in the photo. The gem in the photo is a little over 12 carats. That gem came through our hands back in the mid-1980’s and at the time was worth about $3,000-per-carat. You can only imagine how much it is worth now!!!
Over the past years and especially over the past decade much has been written about spinel so there is at least some awareness of the gem. When we were first in the business spinel was only known to come from Sri-Lanka and Southeast Asia—found amongst the ruby and sapphire deposits. Since that time some wonderful gems have come from East Africa and the Pamir mountains in Central Asia—a mountain range in confluence with the Himalayas.
Andalusite is strange and beautiful and really quite hard to find in larger sizes. Andalusite is notable for a very strong pleochroism with a different color associated with each of 3 different crystal axes. Note the different colors in the gems in the photo. Also note the rough, uncut gems in the background.
For a number of years, years ago, we had a wholesale client who was anxious to buy all the larger sizes of Andalusite we could supply. His demand lasted quite a while. What a wild around the world chase he started. That first year on a trip to Sri Lanka we found one very beautiful Andalusite cut gem that was very large at over ten carats. And then—no more Andalusite in Sri Lanka on subsequent trips.
Later that year on a trip to Brazil we encountered a fellow that had some rough Andalusite. He wasn’t officially in the gem business but his main business took him by some Andalusite mines in the state of Espiritu Santo. These mines were worked as side businesses by coffee growers. Their coffee plantations were very remote and nobody visited the growers and the growers didn’t visit anybody—except for Valdomir. Valdomir sold chemical fertilizer to the coffee growers and had to visit them regularly. He was their access to the world and the man who could bring their Andalusite to the market. For a few years back then Valdomir dominated the Andalusite business and we had an exclusive with Valdomir.
One of the best things about that quest for Andalusite was getting to know the state of Espiritu Santo. The capital of that state is Vitória. Vitória is one of the most beautiful settings you can imagine. The setting is a lot like Rio de Janeiro but without the city sprawl. There are the large inselbergs similar to Sugar Loaf and Mount Corcovado, a beautiful bay and relatively fewer people.
One of the most elusive gems listed as a birthstone is aquamarine. March babies are lucky to have such a wonderful gem as their birthstone on the one hand yet true aquamarine can be difficult and many times very expensive to acquire. You will find in the accompanying picture one lot of cut aquamarine in the manner often used by dealers to show to other dealers in loose gems. Note the distance between gems—to keep chipping from happening. Note the different cuts in the lot. Gem rough is so rare and expensive that gems have to be cut according to the piece of rough the cutter is fashioning from rough to cut. The color of this lot is exceptional. Years ago this was a fairly normal (never common) sight in the great aqua mining regions of Brazil. Not so much anymore.
The size of the pieces is also, always a big issue. Smaller aqua gems like smaller diamonds are always much more in supply than larger stones. Smaller aqua gems are currently available enough that they can be cut into calibrated stones which will fit into standard mountings or in mountings produced in quantity. Calibration is done in millimeters (the gem business being international uses the metric system). Smaller and popular calibrated sizes include 6x4mm, 7x5mm and 8x6mm.
We, at Gems At Large, have been amongst the few who have produced calibrated aquamarine in larger sizes. For many of our larger more exotic rings and pendants we have produced calibrated aqua up to 20x15mm (about ¾ of an inch by just over ½ of an inch). During the past few years however the rough to produce the larger calibrated sizes has just not been coming out of the Brazilian mines. Buying colored stones teaches a person about seizing an opportunity. What we can buy and sell this year may not be available next year. Aquamarine is truly an example of this phenomenon. When great aqua is available and at a fair price—we know to jump all over it!!!
This coming April yet another spectacular diamond will be at auction. This time the gem is a colorless stone of “D” color and is internally flawless. The auction this time will be held in New York at Sotheby’s. The gem is reported to weigh just over 100 carats and has been fashioned into an emerald cut (similar to the stone featured in the photo). Estimates of the price it will fetch are from $19 million USD to $25 million USD. If any of the recent auction results are predictive the price could well exceed the estimates. We will know soon.