What Colour Metal Cores Are There For A Scooter What Do They Use To Colour The Metal Of Body Piercings?

What do they use to colour the metal of body piercings? - what colour metal cores are there for a scooter

A friend of mine gave me a piercing in the new language. It was made of metal, but the color ... and the color came out. Who knows what could have been used for the color?