If you like fluorescent rocks you will really like this. I recently purchased a flat of top grade extreme color changing hackmanite mine rough from Afghanistan for the studio. I noticed that some of the specimens have crater like pits that seem to have burned the rock. In the center of each pit is a bit of green. The top left specimen has a relatively large infection. These rocks are extremely sensitive to ultraviolet light, and the array of colors is not yet well understood. The photo sequence is as follows; WL, MW, SW, LW, FW+WL, Blue Phosphorescence, and deep Purple Tenebrescence (wow!). All pictures taken under the studio UV Breeze with a 35mm lens at F22, ISO 100. I am interested in what you think.