hi mike, i read a couple of your responses on this forum. you seem to know quite a bit about the older crotons. i have a croton nivada grenchen aquamatic. it seems to be from the early 1960s or late 50s. there is a number on the back. it is 8865, on the bottom of the case back it says "aquamatic" and below that it says "14 k gold L&K. it is a 17 jewel swiss movement, and is a self winding watch, it also has a screw down back. the entire case, back and stem winder appear to be solid gold. can you tell me anything more about this watch?