Insider Posted September 10, 2020 Author Share Posted September 10, 2020 1 hour ago, VKurtB said: I'd be willing to bet that polarization would pay big, if somewhat strange, dividends. I see polarizers with new attributes are now out there. Quarter wave retardation was just the beginning. Using a polarizing microscope to examine thin sections of mineral specimens is like playing with a colorful kaleidoscope. Link to comment Share on other sites More sharing options...
RWB Posted September 10, 2020 Share Posted September 10, 2020 Defects in some metallic surfaces can be detected under polarized light - but additions - putty, fillers, oxides, chlorides, etc. easy standouts, and some have distinctive UV florescence. Link to comment Share on other sites More sharing options...
VKurtB Posted September 10, 2020 Share Posted September 10, 2020 1 hour ago, RWB said: Defects in some metallic surfaces can be detected under polarized light - but additions - putty, fillers, oxides, chlorides, etc. easy standouts, and some have distinctive UV florescence. I still have a shorter wavelength UV light, from back in the day when I was into stamps. It was a shorter wavelength that lit up stamp tagging, but not "black light" posters. It also lit up scads of Franklin County, NJ minerals. Might it be useful with coins? I had to wear safety glasses to use it. Link to comment Share on other sites More sharing options...
RWB Posted September 10, 2020 Share Posted September 10, 2020 A multi-spectral examination box is now preferred. Less likelihood of eye or skin damage. Link to comment Share on other sites More sharing options...