A leather bag made from Tyrannosaurus rex cells will be auctioned off on Thursday by Paris auction house Giquello, estimating the “one-of-a-kind” piece could sell for more than US$500,000. Unveiled in the spring in Amsterdam, the bag was created from traces of collagen from the femur of a T. rex found in the US state of Montana 25 years ago. “In recent years, we’ve developed techniques – biotechnologies that allow us to instruct a cell culture to produce, so to speak, genuine T. rex skin in the.