I have just dug an old watch from a drawer where it has been for decades. It was in a bit of a state covered in crud, but I decided to try to clean it up and see if it ran. It cleaned up very well indeed, almost certainly gold and I found it runs perfectly. On one of the strap arms I found what seems to be an Hallmark and wonder if anyone might be able to ID it?
Its an Accurist (possibly) 1960's mens, windup, wristwatch with a small separate seconds dial.
It has a 6 (or a 9) laid on its side, then a > 375. The 375 would seem to indicate 9ct.