Diacalymene ouzregui from Morocco. Lower Ordovician period, approximate 500myo? And the Poulerouter Sub is not a bad vintage either!
Thanks for your kind comments and for thinking of me with this image, Matt. Pefectly matched patina, and we're lucky it doesn't take millions of years to develop. But I better not take the fossil / dinosaur and watch analogy too far. LOL
As others have said, PuristS is only as strong as the people who participate, and it's been great to have you as part of the family. And of course thanks for the great photographs.
Kind regards
Andrew