Tarnished Gold, What Makes it Happen?

Many people that have an interest in gold jewelry and coins often will claim that tarnished gold doesn’t exist, however, that’s the furthest thing from the truth. Pure gold will not tarnish, but it is rare to find jewelry that contains this pure element. When pure gold is added to alloyed gold, such as 18 carat or higher, this will also lessen the risk of tarnishing, with the exception of a few conditions. Tarnishing is generally only seen in smaller carats, depending on the base metals and the elements that each one is exposed to. For example, if a 10 carat gold piece has a decent amount of copper in it, it can oxidize, creating a red or black tarnish. Silver also exposed to the elements when combined with gold produces black tarnish.

So what causes tarnished gold? When gold is mixed with these base metals, as it almost always is, exposure to environmental factors that are going to have an effect on the metals. Moisture, organic vapors, oxygen and sulphur compounds in the atmosphere, and even human sweat and oil from human touch can make gold tarnish if it is mixed with a high amount of base metals. Surprisingly, perfumes and deodorants with certain chemicals in them can also affect gold to a point that it will tarnish.

One of the most surprising offenders that cause gold to tarnish is certain food products. Pickles, fruit juices, onions, and other items with high acidity or sulphur compounds are likely to create a tarnishing affect on gold that is less than pure.

Sometimes the way a piece of jewelry or something made of gold is manufactured can have an effect on its susceptibility to tarnishing. Items that are cast by lost wax casting and other methods that leave a micro-porous surface can actually cause the jewelry to trap various acids, compounds, and other elements which will cause a form of local tarnishing wherever the foreign impurities gets trapped.

Jewelry can be kept from tarnishing by storing it in a pouch or bag in a dry atmosphere. You should also polish your jewelry regularly to remove contaminants and other inconsistencies. You can even have the item electroplated with pure 24 carat gold which will prevent tarnish for awhile, but will eventually wear through with use and age. Some countries such as India and the Middle Eastern countries do experience a blackening of higher carat gold pieces, and no one seems to know the cause. Generally, it is related to a different lifestyle and condition or environment, since the problem doesn’t occur elsewhere in the world, but no one knows for sure.

When it comes to coin collecting, many consider a bit of tarnishing, or toning as it is called in collecting circles, to be highly desirable. Gold coins rarely tarnish because of their purity, but some exceptional toned coins exist and this toning makes them all the more valuable. You may want to clean your jewelry to have it restored to its original shine, but all coin collectors know to never, ever clean the tarnish off their coins. In fact it is a general rule to not clean your coins in any way. Collectors desire the antique look of an old coin and want that look preserved. Cleaning highly collectible gold coins can ruin their value.

Just remember it is perfectly okay to clean tarnish off of your beautiful jewelry, but never clean the tone off of valuable old gold coins. Stick by these rules and keep your gold valuables of any kind in the best condition and highest valuable possible.