I've had some of these fossils for years now, but reading this thread made me doubt the authenticity of some of them. The first is an unidentified fish fossil I purchaed from a small shop in drumheller claiming to sell fossils. From what I remember, the woman selling the fossils was worried that I was going to break one of the fossils and kept staring at me like a hawk. The mosasaur and pavlovia fossils were from a shop in Banff, which is really popular for purchasing fossils and the papers are supposedly certificates of authenticity. I trust the source, but I did read a thread about fake mosasaur teeth and the 'pavlovia fossil' (not sure if ID is correct or if that was for an entirely different fossil. I don't keep my papers with my fossils because my fossil display is cluttered without them. It's possible that this is the fossil I purchased from some metaphysical store in Toronto.) was inexpensive for such a fascinating specimen ($10-20 Canadian, if I remember correctly). The trilobite was my first largish fossil and it was purchased from a store in Jasper. The lady at the store was somewhat knowledgeable about the specimen, so I think it's probably authentic.