How fast does a cartilage piercing close up?

Well it depends on how long the piercing has been in place. If it's new and you had a change of heart, the piercing will close up within a few days of the jewellery being removed. However the hole in the cartilage itself will remain open for several months. Cartilage doesnt heal like skin and once it's pierced or damages it can take and extreamely long time to heal.