This economical shortwave ultraviolet fluorescent lamp now also includes a longwave ultraviolet LED lamp so you can experiment with both shortwave and longwave ultraviolet light. Shortwave ultraviolet light is just the right wavelength to vibrantly illuminate many fluorescent minerals that you collect. Some minerals fluoresce or glow, under shortwave ultraviolet light, others under longwave ultraviolet light, and others fluoresce differently under both! This one economical, portable provides both shortwave longwave wave light.