In an effort to work out a problem with my spectrometer I have a few minor cuprian tourmaline gemstones out of storage. One of the gemstones is particularly close to my heart. I bought the rough after the great escalation in price for the very limited amount of cuprian rough that was available from Mozambique. It was not expensive because it was at best a semi facet grade piece of rough and had a mixture of colors, between significant feathers. The colors were the classic mixture, for unheated cuprian tourmaline, of green, blue with a touch of gray and purple.
When I start to work up a piece of rough like this I do not spend a great deal of time before I start removing material that can not be saved. This usually means grinding down the feathers that have a low angle to the nascent tables plane first. In this case it meant he complete removal of the green portion of the nodule. I like to orient the remaining naturals as perpendicular to the nascent plane as possible, but in this case the remaining flaws formed a pretty much a three dimensional maze that would not prove to be particularly damaging to the beauty of the finished gemstone. This did give the freedom to position the table for maximum yeild. Unfortunately it require the removal of the most richly toned purple areas of the gemstone. I say unfortunately because I find the purple blues of cuprian tourmaline much more exciting then the straight blues. The are more exclusively cuprian colors and help to fill that hardest of parts of the color cycle, blue purple, for tourmaline.
Now I am a bit disappointed that I am down to what appears to be pretty much a grayed blue, but I have cut enough of this material to realized that it is hard to gauge its potential beauty while the stone is doped to an aluminum stick and seen under incandescent light. As I cut the standard round brilliant from the remaining material, I like that none of the flaws cause problems at the surface or interfere with the polishing. Still it will be definitely included.
So the moment of truth comes for the 3 and half carat stone when it is removed from the dope and cleaned. Wow it is a hit with me. It has a lighter medium tone of blue purple, under natural light, that is a very nice addition to the collection. You probably noticed that I said under natural light, because yes it turned out to be a Laurellite (see other posts) and it looses the purple completely under incandescent light. All of this fun and excitement for relatively little cost! That is hard to beat, but the trade would not leave this stone alone.
Now I am talking about treating this rather nice middle grade cuprian tourmaline to meet the market’s demand for a “neon” blue, flawless gemstone. I am not a heater, but I am sure that the purple could be removed by heating and probably a lot of the grayish cast. The stone might crack during the heating process, but if the web of naturals in the existing gemstone is the only clarity issue, epoxy can really eliminate a great deal of the problem. It would also eliminate any hope of having an appreciation of a truly natural gemstone with only cutting and polishing between it and the ground.
I find the gemstone a truly unique example of the diversity of tourmaline and the naturals are not excessively distracting to me. I also think that the average collector would find a heated and epoxied gemstone more exceptional when compared to other gemstones. Of course he should pay less for the stone than a naturally cyan colored one that is unheated or enhanced with epoxy. And with the treatments revealed, but that is another story.
I took you down the long path cutting, polishing and speculating because I wanted to give you a feeling of why this gemstone is personal to me. It is a path that no one else can follow. But if the gemstone is permitted to stand as it is and I personally wonder about the future, it will still display the unique phenomenon of reverse alexandrite color change and have some appreciation of the effort I put into the gemstone threw the orientation of the naturals (not too important in this case). Perhaps when it is heated and treated it might just as well have been man made? It certainly is a personal judgment.
I am enough of a chemist to think that the economical, laboratory creation of tourmaline in reasonable pieces is still pretty far away. But it will happen and a wonderful rainbow of colors in a viable gemstone will become available to the trade. The likes of which have never been seen before and I will glory in that, but I will still be a natural man. Still with just a bit of heat ….