Sometimes, as jewelers, we are asked if our jewelry is made of pure gold.  Technically speaking, only gold with no additives can be called pure. Pure gold (24K) tends to be too soft to be used for jewelry.  So various metals that acts as hardeners such as silver, copper, nickel, palladium or zinc are added to make gold suitable for jewelry use.  Once these metals are added at a refinery, the entire mixture is called an alloy.  Almost all gold used in jewelry is an alloy to varying degrees.

If your skin turns black underneath gold jewelry that does not mean that it is not “real gold”.  The problem is not that uncommon and is known to jewelers as “gold smudge”.  It is commonly caused by a chemical reaction between the piece and the wearer, or from tarnish.  While 24K gold does not tarnish, some alloys will. Although 10K is legally the lowest karatage that can be called gold in the U.S., England manufactures 9K gold jewelry and Germany has 8K gold. Lower karat gold pieces will go dull or even turn black merely from exposure to chemicals in the atmosphere.  They will also discolor in contact with perspiration, some fabrics, bleach and other household chemicals. Both 18K and 14K jewelry are less likely to smudge than 10K, due to the fact that the higher karatages contain less base metal. Buying jewelry with a higher karatage will help. Upgrading to a better alloy such as 18K usually solves the problem.

The number one alloy that the most people have a problem with or are actually allergic to is nickel. The next most common cause of allergies for jewelry wearers appears to be detergent or other chemicals which lodge between the jewelry, usually rings, and the skin. The most common chemicals are perfume, hair spray or deodorant. Some jewelry will tarnish in storage over time.   Another tarnishing agent may be the preparation of vegetables such as onions and spices as many foodstuffs contain sulphur compounds and others are acidic.  Smudging is often accompanied by skin irritations such as rashes and flaking skin as well. Regular cleaning and careful wear often eliminate the problem.  Rinsing well can help but it is best to remove rings before using any troublesome chemicals and/or use a barrier cream for skin or barrier coating for inside contact areas on the piece of jewelry.