A few days ago I explored Mam Tor with Eivor and popped into the nearby cave looking for treasure, as per. Now it happens that I've been to Mam Tor a few times in real life (GCSE Geography initially, FYI), and have gone into the caves by Mam Tor, which is why I recognised the blue/purple veins in the rock walls as unmistakeably being Blue John, the mineral which is only found in the immediate vicinity of Mam Tor and nowhere else in the world. And this is the only cave in the game that has purple crystals in the walls so someone specifically designed that, just for this cave, just for that geological accuracy, for no particular plot reason, and that person deserves a cake or something. Ubisoft, find that person and give them a cake, because I never expected I would ever yell "THAT'S BLUE JOHN!!" at 11:30 at night. It gave me joy!