The best thing to do is call them directly and find out what their policy is. I believe there are State laws and Shop policies they strictly follow.
I agree with Tina.
Personally, I wouldn't. Cartilage piercings tend to hurt more, I know because I have 2 of them. Plus, if the area is not properly cleaned after piercing you run the risk of infection. Bottom line, you know your teenager best, if they are mature and can handle it, then ultimately it is your decision.
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