Tag Archives: Gem Cutting

The Giant Kunzite Crystal

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kunzite big roughEdited Kunzite Sawing photoKunzite group photo rough to cut

720 ct kunzite

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.

John and Laura Ramsey write: Andalusite a Strange and Beautiful Gem

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gem pictures 029Andalusite 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.

John and Laura Ramsey write: Aquamarine an Elusive Gem

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Aquamarine, color gemstone, Rio de Janeiro, Brazil

 

 
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!!!

John and Laura Ramsey write: The Joy of Buying Rough Gems

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Aqua Crystal

One of the most fun things I can imagine is buying gems in the rough uncut form. In the picture you can see a fabulous rough aquamarine crystal. In this case we’re talking about a piece almost 5 kilos in weight (11 pounds), about 20 inches tall and its worth (?)—priceless as a work of nature’s art. Not all rough aqua is this large, fabulous and crystal clear but when it is what a treasure to behold! Not all that long ago I was offered a parcel of rough (known in the trade as a “lot”) —also aquamarine—but even darker blue with wonderful crystal shapes. Some of the pieces in this lot were acid etched by acidified water in the surrounding soil. Acid etched crystals are often very shiny and can have curious shapes as compared with the more classic crystal form of aquamarine. It is unimaginably exciting to find a lot of rough gem material offered that I know, as a gem cutter, will cut into large, clean, top color gems—what a thrill that is. The best way to share this is to be able to pass them on to collector clients as the finished piece—either as a loose gem or in a piece of Laura designed jewelry.

John and Laura Ramsey write: Tsavorite a Wonderful Garnet

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tsavorite picture

We’ve shown a lot of garnet photos over the past few weeks. One of our favorite garnets is Tsavorite which many Gems At Large aficionados know is named after Tsavo National Park in Kenya. We’ve been in Kenya buying rough Tsavorite as early as 1977—directly from the mine owners. I remember cutting some of my first experiences cutting Tsavorite go back even further to as early as 1974—not that long after its original discovery. Commercial mining of Tsavorite is reported to have begun only in 1971.
What a beautiful color of green we get to see in Tsavorite. Tsavorite is a color variety of grossular garnet—which is a calcium rich garnet. Initially gemologists assumed that the green color was caused by chromium as is the green color in Emerald and Demantoid garnet. Oops. It turned out that it is vanadium that gives Tsavorite its color.