The Definitive Guide to the World of Color in Tourmaline Gemstones

The Definitive Guide to the World of Color in Tourmaline Gemstones

Kenya, golden yellow/orange, and breaking up is easy to do.

Posted by: Bruce Fry Tourmaline Collection

August 12, 2021

Some relationships are not worth pursuing and other ones will stand the test of time. In 2020, the year of the virus, it became very difficult to obtain rough from the only supplier that has weathered all the storms for twenty years. I hungered for work and a breath of fresh color, so I was forced to test unknown waters. The subject of this post is the result of one of my test purchases. A new hope that turned out to be both an old friend and a broken promise.

Tourmaline from Kenya.

The piece I just attempted to cut came in a lot of 8 pieces and was advertised as coming from Mozambique. Now Mozambique is my favorite place in the world for tourmaline. It produced the wonderful array of cuprian colors that grace my collection along with a rich expression of other tourmaline colors. But I had never seen a rich golden yellow to orange from there before. So I put my money down.

When the lot arrived and I looked at it closely, I thought I recognized an old acquaintance. When I questioned the supplied about its origins, he confirmed that did not come from Mozambique, but from Kenya. Now I love the vibrant well-toned golden yellow/orange color and the rough appears both clean and blocky, but in its heart, it has stability issues. And I am not talking about the development of a small veil or two, but unacceptable cracking. The following meltdown deals with one of the larger rough pieces. I did not weigh it, but it certainly came in over a fat gram.

The piece of rough was relatively long and narrow. It had a thicker end and a relatively thinner end that was still useful. The piece appeared to have a natural weakness that produced a blocky piece that had been heavily cobbled by man. To obtain the widest gems I could, I decided to grind off one of the long edges of the basically rectangular solid. The grinding of the nascent table went well, but as I proceeded, I realized that the thinner end was too narrow in comparison to the thicker end, to cut an emerald cut efficiently. This left maybe losing a third of the piece to make a decent-sized round or slicing the piece. Now I never like to use my diamond facet saw on rough. It guarantees I will not get a good yield, but this piece demanded it. The cut was well placed and I now had the potential of two rounds in the four to six mm range. When I now looked deeply into the larger piece I could see some random lightly feathered areas, but nothing that indicated a significant flaw.

The first moment of failure was during the grinding of the girdle of the larger piece. The new flaw which was highly reflective was steeply inclined in relation to the girdle, did not extend completely into the body of the piece. With some hope for a nice stone, I ground down the girdle. This produced a much small stone with only a very faint tail of the fracture still in the stone. Here is where you either accept the feathers a get an included gems or throw the junk away. I chose to finish the pavilion and everything went well. The vivid blend of the oranger c axis and the golden yellow a/b axis certainly sparkled under the polishing lap.

The second act of fracture occurred after I had transferred the gem and started cutting the crown. The resulting obnoxious highly reflective flaw, a continuance of the flaw I had tried to grind out, was unacceptable. I thinned the girdle and dropped the main’s angles, but I could not make an acceptable gem. Defeated again, for this material has a history of frustration for me, but the color still calls me back, I accepted my fate. There is still the potential for a small round and maybe I will try cutting it someday, but for now, it will sit on the window of the lost in my kitchen.

I will still keep reaching for color.