We use a brass alloy of copper, zinc and silver that is free of some toxic substances such as nickel, lead and cadmium. We do not recommend brass for new piercings. For some people, it can cause irritation.
Keep in mind that the skin and jewelry may discolor green, but the color is usually the result of a metal in the jewelry that reacts with your skin - or something on your skin, such as hand cream.
The acids on your sweaty skin (or in your lotion) cause copper in the brass to corrode, creating copper salts. This blue-green compound can leave a mark on your skin.
Other metals can produce similar effects: Silver in sterling silver, which is used as an alloy in a lot of gold jewelry, can be oxidized when it comes in contact with the skin. This causes discoloration and may leave a dark green, brown or black spot. Although these brands are often associated with cheaper jewelry, they can happen with the expensive products as well.
The good news is that even the hardest discolored brass part, you can simply clean by leaving it for up to 30 minutes (if it is very discolored) in Ketchup and water! The jewelry will be like new!
Removing your jewelry before showering / bathing also reduces the risk of discoloration.