This was a rather interesting experience. Purchased by myself in February 2017 after a stint of looking at the International Mineralogist Association's list of fluorescent minerals on fluomin.org . There were quite a lot of minerals that I had never even heard of and unfortunately most weren't being sold on eBay at the time. However, one of the ones that I came across was kratochvílite from a Czech seller. He also was able to take decent UV photos of his specimens. Enough to show me that I wouldn't get skunked on a non or dimly fluorescent variety of the mineral as often happens in the hobby. It was a match made in heaven for me. It's hard to emphasize how hard it is for dealers in a country outside of the US to get good fluorescent photos simply because all of the "name brands" in this hobby are based in the US. With that information in tow I asked him about several minerals that were on the IMA list. His prices were very reasonable so I just asked him to show me the best of the best of those species. This is what he showed me. An absolute best-in-class specimen of kratochvílite that's better than anything I can find documented on the internet. Came from his personal collection. It is both the richest in terms of overall saturation of kratochvílite and has multiple large pockets of pristine crystals.
Locale: Kladno mine, Kladno, Czech Republic
Dimensions: 114 x 60 x 56 mm