A few words about Ultraviolet Lamps:

The inexpensive ultraviolet lamps (commonly called "blacklights" - they use "BLB" bulbs) sold in novelty shops produce only longwave ultraviolet (UVA) rays, along with a good deal of visible blue. A scientist’s (or serious hobbyist’s) longwave lamp will have considerably more power, and produce significantly less visible blue light; it will also be much more expensive than a "blacklight". Longwave UV rays are generally considered to be not harmful to eyes or skin.  Junior rockhounds can use longwave or 'BLB" lamps without worry (although it is always a good idea to have a parent supervise their use).  The powerful "blacklights" sometimes used at rock music shows, and sold for use in lighting up posters, etc., are also longwave-producing lamps, and are safe to use as well; they cost significantly less than a serious researcher’s longwave lamp.

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 somewhat 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 longer period 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 eBay auctions advertising low-powered, relatively inexpensive shortwave lamps as safe, as long as you "simply don’t look into the light"; please don’t you believe it! First, many 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) do a good job of protecting young eyes.

Now for the 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 $200, and a more powerful display lamp can run up to $1000 or more.  Make sure that 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.

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