When I was growing up, the men I knew did not wear jewelry other than their wedding band, class ring, or dog tags from military service. However, today jewelry for men is a growing market in many segments of the population. It is no longer considered unmanly to wear jewelry. Men wear rings, bracelets and necklaces routinely.
So while it is true that my father does not wear jewelry, many other men that I know, do. One of the most popular growing jewelry items for men to wear are precious metal dog tags. Dog tags as jewelry have grown out of the usage by the military for dog tags as ID badges. Soldiers can wear them under their clothes, and they are hard to destroy, so that they can be identified.