Is it proper for a man to give jewelry as a gift to someone he is just friends with?
Why not? A gift has only the meaning that the people involved
give to it. A book (or almost anything else) can have a much deeper
meaning in a relationship than even a wedding ring. And depending
on the occasion, a piece of jewelry, like a classic watch can be
something really wonderful and commemorative. If your friend is
getting married, got a long-awaited promotion, had a child, or did
something else that warrants a major congratulations, absolutely go
ahead with jewelry.