This is a piece of Fluorite. This original image is quite dark because Fluorite is translucent, and not much light returns from it.  This image has been stretched to brighten the image, and the bright colorful spots are saturated glints in the various colors.   The sample is placed on a black anodized aluminum plate. The illumination was by the red, green, and blue LEDs in the optical head.  This image is a composition from 3 monochrome images. The individual images are shown in thumbnail below. Clicking on the color name will take you to a full size view.  The UV image shows the fluorescence of the mineral. 

             Red ( Full Size View)                             Green ( Full Size View)                        Blue ( Full Size View)                            UV ( Full Size View)