My daughter's navel jewels make me mad.
Apparently, it serves some positive feeling for her, she shows it off in the summer, making me madder.
I see men with ear rings, which causes a stir inside me. Tounge beads also make me wonder what is going on. I am informed some wear jewelry in unmentionable places.
So your questions intrigue me. I did a Google search on jewelry effects, and found other unmentionable parts of the body with pins and jewels inserted, but for reasons broadly classified as fashion, health effects (copper bracelets), mystical beliefs, religious beliefs, superstition, and demonstration of wealth.
How does it make people feel? Those reasons will spark the whole range of human emotions.
A lot of this has to do with where the person is as well. Some jewelry, as Bob mentioned, is taboo to certain groups of people. Others is not. Some is taboo to some groups of people and not others.
Generally speaking, no matter what, you wear jewelry to get it noticed ~ whether for shock value or as a thing of beauty. It can also be a status symbol if it is expensive jewelry.
Speaking as a "jewelry junkie" and having worked in a high-end jewelry store, I only ear jewelry as earrings, pendants, pins, rings in the "usual" places! For me, it was just having certain pieces of jewelry and not necessarily wearing them. In fact after I lost a very expensive diamond earring, those are in the safe because the replacement cost becomes more expensive each year.
Having observed the many customers in that jewelry store, where the jeweler designed and made exquisite pieces, we would get literally "sick" at the people who were wearing one of his "works of art" and trashed them. He used to say "never wear your jewelry where you don't wear your shoes - not swimming, not in the shower, not to bed, etc.
My husband also collected unset stones. I eventually traded them later at another jewelers who now does all my repairs free and let me choose a couple of his pieces.
If you are considering jewelry as an "investment" don't! Many older people try to see "estate pieces" and get little to nothing for them. The price of gold, for example, has gone "out of sight" price-wise so many people are now wearing silver.
One of my nieces prefers white gold, which looks like silver but all my nieces got what they wanted. You can tell I never brought any money home from working in that jewelry shop, but some lovely jewelry! It just happened to be better for me than a salary!