The tag implication #66332 piercing -> jewelry is pending approval.
Reason: The term "piercing" is almost always used to refer to a piece of jewelry worn in a body part that has been pierced, or at least used that way often enough that I feel the implication makes sense.
Edit: There are piercings that aren't considered jewelry, such as ear_tag, so I wouldn't recommend approving this implication; I've made one for ring_piercing -> jewelry instead.
Updated