my sons class ring was stolen

My oldest son got his class ring a couple months ago. He put a lot of thought into what he wanted on it how he wanted everything. He wore it every day he loved it. But yesterday when he was getting into the car at a friends house this 20 year old low life who lives by his friend and doesn't like my son decided he was going to grab him out of the car told him to give him all his things. Before my son could do anything this low life grabbed the ring off his finger & ran. I usually don't wish anything bad on anyone but I want jerk to rot in hell!!! How low & desperate does someone have to be to steal a class ring from a 15 year old?! I'm just rather pissed right now but at least I got insurance on it so I can replace it.