The helix piercing is a perforation of the helix

Helix (ear)

The prominent rim of the auricula is called the helix. Where the helix turns downward behind, a small tubercle is frequently seen: the auricular tubercle of Darwin....

 or upper ear (cartilage) for the purpose of inserting and wearing a piece of jewelry. The piercing itself is usually made with a small gauge hollow piercing needle, and typical jewelry would be a small diameter captive bead ring, or a stud.

Sometimes, two helix piercings hold the same piece of jewelry, usually a barbell

Barbell (piercing)

Barbell style piercing jewelry is composed of a straight bar and with a bead on each end, one or both beads unscrewable for removal and/or changing of the beads. Often one of the beads is fixed, either via epoxy or welding, so that only one bead is used to install or remove the jewelry...

, which is called an industrial piercing

Industrial piercing

An industrial piercing , sometimes called scaffold piercing or construction piercing, is any two pierced holes connected with a single straight piece of jewelry ; however, it typically refers to a double perforation of the upper ear cartilage specifically...

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A sterile needle is pushed through the cartilage and then kept in while the jewelry is added.