Why Do Metals Tarnish?
Jewelry Storage could help
There are many conditions that will cause metal to tarnish. Humidity, sweat, salt air, sulfur, hairspray, makeup and household chemicals are common things that might come in contact with your jewelry and cause it to change color.
An article I read recently addresses another reason for tarnished metal called galvanic corrosion. It occurs when different metals are put together, either in storage or when mixed in a piece of jewelry. I won’t go into the science, but it has to do with charged particles moving between certain metals. This can happen very slowly over many years, or it can happen very quickly, depending on the surrounding environment.
As a jewelry designer who loves mixed metal jewelry, this explains some things. For example, a copper and silver pendant that I made, formed a dark halo on the copper, but only surrounding the silver part. This happened no matter how much I cleaned or sealed the copper. Silver is one of the metals that will cause copper to corrode or change color.
Lately I have been recycling stainless steel rollers from inside video cassette tapes. One of my earring designs has copper twisted around the stainless steel. I noticed that the stainless steel had become a very dark gray under the copper. Sure enough, copper is one of the metals that will tarnish stainless steel.
Another example is that sterling silver can tarnish aluminum. Aluminum jewelry, especiallty aluminum wire jewelry, has become very popular because of its light weight, low price and anti tarnish qualities. However, storing your sterling silver jewelry with your aluminum jewelry could cause the aluminum to turn dark or black.
My advice is to be aware of this phenomenon and to store jewelry made of different metals in separate places to prevent tarnish. I recommend plastic bags or airtight bins to keep out humidity and other airborne chemicals.