When purchasing new jewelry, many people wonder, "Will this piece tarnish?" Following is quick overview of what tarnish is, how it happens, and which metals are more or less prone to tarnish.
WHAT IS TARNISH?
In the jewelry industry, tarnish is defined as a thin layer of corrosion that results from a chemical reaction between a metal and a non-metal compound such as oxygen or sulfur dioxide. A thin layer of corrosion forms over the metal, which mars its shine or gives it a black or greenish hue. With the exception of pure 24 karat gold, platinum, rhodium, and stainless steel, most metals used in jewelry can tarnish over time.
HOW TO PROTECT YOUR JEWELRY FROM TARNISH
To minimize tarnishing, jewelry should be stored in a protective jewelry box or pouch when it is not being worn. Leaving jewelry out in the open speeds the tarnishing process due to exposure to the air. Store your jewelry in a sulfur-free container that is designed for storing jewelry. Any amount of sulfur in fabric, thread, glue, or paper will cause tarnish.
WHICH METALS TARNISH?
Pure 24k gold does not combine easily with oxygen, so it will not tarnish. 24k gold is normally not used in jewelry because it is very soft and does not hold its shape well. Pure gold is alloyed with a stronger base metal to create 14k gold, which is more rigid, but still not likely to tarnish. Lower karat gold, such as 12k and 10k are more likely to tarnish because they have less pure gold and more base metal. Tarnish occurs when a base metal interacts with oxygen and/or sulfur. The lower the karat, the higher the base metal and the more likely the piece will tarnish.
While pure silver is naturally tarnish resistant, like pure gold, it is too soft for jewelry applications. Sterling silver is 92.5% silver mixed with 7.5% of another metal, usually copper. It is the copper or other base metal that causes silver to tarnish when it reacts to moisture and sulfur in the air. Sterling silver tarnishes faster in places that have a high level of humidity or air pollution. Silver also tarnishes faster when it comes in contact with harsh chemicals contained in things like perfume, lotion, deodorant, and hairspray.
Argentium is branded alloy of silver that is quite tarnish resistant. It has a higher silver content than 925 sterling silver and is alloyed with a unique combination of metals that gives it a naturally bright, durable, and tarnish-resistant finish.
Rhodium is a beautiful silver-white precious metal that does not tarnish. It is the most expensive of all precious metals. It is extremely durable and has a brilliant mirror-like finish. Unlike pure gold and pure silver, pure rhodium is extremely hard. In jewelry, rhodium is used provide a beautiful, tarnish-resistant finish to silver, brass, and other metals. While rhodium itself does not tarnish, rhodium plating can wear off over time and expose the base metal. When the base metal becomes exposed, tarnish can occur.
Stainless steel is becoming more popular in jewelry applications - especially in men's jewelry. Stainless steel will not tarnish. It is, however, quite rigid and heavy. Stainless steel can look nice and is quite affordable. When shopping for pieces online, be sure to check the weight of the product before purchasing.
DOES PLATED JEWELRY TARNISH?
Whether plated jewelry tarnishes depends on the material used for plating and on wear and tear. Jewelry that is well-plated with Rhodium or 14K gold will not tarnish until the plating wears off. Plating can wear off over time due to bumps, scratches and rubbing against other items or materials.
Jewelry that is plated with sterling silver is prone to the same level of tarnish as solid sterling silver. Once the silver plating begins to wear off, additional tarnish or is likely to occur when the base material becomes exposed.
HOW TO CARE FOR PLATED JEWELRY
Treat your plated jewelry with care. Avoid contact with harsh chemicals in makeup, lotions, and other beauty products. Avoid contact with water - chemicals in treated water can cause the plating to wear off faster. Store your jewelry in a jewelry box or pouch in a cool, dry place when it is not being worn. To clean plated jewelry, very gently wipe - do not rub! - the surface with a soft jewelry cloth. Never use a polishing cloth on your plated jewelry a this will strip the plating away.
HOW TO REMOVE TARNISH FROM SILVER OR GOLD JEWELRY
Tarnish can be removed from silver and gold by polishing with a small amount of phosphate-free dishwashing soap and warm water. It can also be wiped away with a professional polishing cloth or a tarnish-removing formula. Do not use any abrasives like baking soda, toothpaste, or coarse brushes to clean your silver and gold jewelry. Certain stones also require special care. When in doubt, ask your jeweler for guidance on how to clean your finished piece.