Roger Weller, geology instructor
Conclusion and References
Although my camera is obviously not a high quality optical machine especially designed for still-life macro photography, one can easily distinguish between the ambient and the ultraviolet light colors of the minerals of Cochise County presented here. The goal of this presentation is not to provide high resolution views of mineral structure and crystalline characteristics, but to show the beautiful and brilliant array of minerals found within Cochise County, Arizona. And to introduce the reader to the wonders of fluorescent minerals that may be as close as their own back yard or driveway.
The shortwave ultraviolet light used to view these specimens is a wave length of 200 to 300 nanometers. Minerals that display one color under shortwave light often, but not always, display another completely different color under longwave, 350 to 380 nanometer, ultraviolet light.
My question to Roy Parsons while we were photographing his mineral collection was; “Is their one light that has a variable wavelength, something with a sort of rheostat that allows a person to twist a knob and emit the whole spectrum of ultraviolet?” To my surprise, Roy said such a light does exist and is called a Monochromator Xenon Arc Light. I was surprised to learn that such an instrument actually existed but, I wasn’t too surprised to learn that Roy owned one.
Cochise County is, from a mineralogy and geology standpoint, a very unique
location without the consideration of minerals beyond the visible light
spectrum. When one goes beyond the extraordinary examples of copper ores in
Cochise County and begins to explore and delve into the world of ultraviolet,
Cochise County evolves form extraordinary to truly astonishing.
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Calcium fluoride (CaF2) is an insoluble ionic compound of calcium and fluorine. It occurs naturally as the mineral fluorite (A.K.A.: fluorspar), and it is the source of most of the world's fluorine. en.wikipedia.org/wiki/Calcium_fluoride