I told you some time ago that I would write you about my experiments with Cobalt-60 irradiation of insulators. I've had mixed emotions about the whole thing because of the fact that the radiation does change the color of some types of glass; and, although I have stressed the fact that the ones I've traded have been artificially colored and are FAKES, I know of at least one and maybe two that have been traded off with no mention of the facts behind the color. A couple of ads that have appeared lately sound as if someone else might have access to an irradiator, too, but then again the colors being offered might be true. I certainly don't want to hurt someone's chances at some good trades, but neither do I want people trading high for something that is common but artificially colored.

Anyhow, Cobalt-60 radiation, which is used in the treatment of cancer and in research and industry to promote chemical reactions, is exactly the same as high powered X-rays. These rays react with some types of glass to change its color. Even though the radiation comes from a radioactive isotope, the material being irradiated does not become radioactive, so there is no danger in handling these pieces.

I haven't tried all types of glass, but I do know that PYREX comes out a beautiful dark tea color. Clear glass, like the common Hemingrays, also turns sort of an amber. 7-Up green Hemis come out almost black; while the plain old aquas, both Brookfield and Hemis that I've tried, really don't change much, maybe from the aqua to more of a gray green. Of course the intensity of color produced is related to the length of time in the irradiator: the longer, the stronger. The process is reversible. If the irradiated glass is heated or left in the sunlight, it tends to fade. I know that heating laboratory Pyrex glassware in a bunson burner flame will clear away the color completely, but I haven't done any precise testing to tell just exactly the temperature required. Unfortunately, my laboratory no longer has the irradiator, and I can't produce any more Fakes. Maybe that's good. I've used them mainly as mementos (mainly HEMINGRAY-14, CD 160) of visits with other collectors, but have traded some PYREX, CO 128 and saw one at Colorado Springs meet last summer that the owner swore was a true color; but I knew it was one of mine because I recognized the exact embossing, even to the imperfections in it. Soooo, let the buyer or trader beware.

Dennis McHenry

A big Thank You to Dennis McHenry for the above article concerning the color treatment being applied to insulators and also to bottles. I have seen these color treated articles at several different shows and have been doing my best to find out how it was being done, so that I could write an article, but anyone doing it around here was not about to give me any information for just that reason. I didn't want to start any panic, so I wanted to be sure of my facts.

It's a shame that these things do crop up in our hobby. Perhaps a National organization could be of help on fakes and reproductions not marked as such. There is nothing so discouraging as being taken in by an unscrupulous person and paying a big price for an insulator not in its original color or condition.

Your Editor