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TIGEROWNER MINERALS
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A few words of caution about Ultraviolet Lamps: First, let's discuss longwave UV sources. The inexpensive ultraviolet lamps commonly called "blacklights" which use "BLB" bulbs and are sold in novelty shops produce longwave ultraviolet (UVA) rays, along with a good deal of visible blue. Junior rockhounds can use these "blacklight" lamps generally without worry, although it is always a good idea to have a parent or other adult supervise their use, especially those which use an AC electrical source, which tend to be higher wattage, and which can get hot after being used for a while. Recently a new product, the Convoy S2 365nm flashlight, has dramatically changed the longwave scene for hobbyists. This device is an LED longwave flashlight, powered by a rechargeable battery, which will project a very bright, tightly-focused beam of longwave UV at 365nm - this beam is so powerful that it is dangerous to point it directly at anyone's eyes, and any young rockhound's use of it should be supervised... A separate class of longwave lamps are those intended for scientists or serious hobbyists - these will typically have considerably more power, and produce significantly less visible blue light; they are also much more expensive than "blacklights". Incidental longwave UV rays are generally considered to be not harmful to eyes or skin (assuming they are not directed at full power into a person's eyes!). Shortwave (and midwave) lamps are a different matter entirely! Shortwave UV lamps produce shortwave (UVC) rays, which are the type that can quickly produce a "sunburn", or "welder’s flash" (which is basically a "sunburn" of the eye). Midwave lamps produce UVB rays, which are also considered dangerous, although less so than UVC - in fact, midwave UVB lamps are used in certain medical therapy applications. High exposure to UVB or UVC rays over a period of time is thought to promote skin cancer, and possibly to produce cataracts. These lamps should always be used with eye and skin protection. Unfortunately, I have seen advertisements for low-powered, relatively inexpensive shortwave lamps which characterize these products as safe, as long as you "simply don’t look into the light"; please don’t you believe it! First, some adventurous children, when told not to do something, will simply wait until you’re looking the other way, and then do it! Second, anything you shine the lamp on will reflect some of the shortwave rays – right into your eyes. And finally, lower-powered lamps require total darkness to be effective; however, the lower the level of ambient light, the more your pupils will dilate – thus letting even more shortwave UV into your eyes. Fortunately, most safety glasses (check the label for UV protection) will do a good job of protecting young eyes. BTW, it's not just your eyes with which you need to take care: A shortwave UV lamp, depending on its power, can produce a severe "sunburn" on exposed skin in a remarkably short period of time. Now here's some good news! Used with care, and with adequate eye and skin protection, shortwave and midwave lamps are wonderful tools that produce brilliant fluorescence in many more minerals than longwave lamps can. Because of this, most rockhounds who really get into this hobby eventually "graduate" from longwave lamps to shortwave (midwave as well); this is fine, as long as they treat these tools with the respect they deserve (and use the proper safety precautions). Their major drawback is cost: a good battery-operated shortwave or midwave field lamp can cost well over $2-300, and a more powerful display lamp can run up to $1000 or more. Make sure that you or your junior rockhound is ready for this type of lamp before making the investment; then make sure that it is always used with the proper safety precautions and adequate eye protection. |