LB – Only the Kohain Godol wore the Choshen (the breastplate that you are referring to). There was no jewelry for a regular Kohain.
There is some relation of men’s watches and jewelry because of the issue of carrying on Shabbos and a man’s watch that is broken, no? I know that a woman can continue to wear a watch that has stopped because it is jewelry but a man cannot (for the same reason?). Can someone elaborate on this aspect of men and jewelry?