Hi, Everyone! I just have to add one thing to this discussion. I was having trounle ith the Phillipine specimens of Conus pertusus fading badly, even when kept in complete darkness. Then a dealer told me to soak off the usual oil, then spray them (the new ones I had received) with Wd-40. They re still brightly colored after 10 to 15 years. I spoke to one of our malacologists about this, and he said that in this case, fading was probably due to pigment oxidation, and the WD-40 was preventing air from getting to the shell. I have used it on a few other shells, as an experiment and have noticed no other result than I ould with our usual concoction. However, most of my shells are in plastic bags or boxes, so they don't tend to get dusty anyway. Cheers, Linda