The chains and findings I use in my work are all sterling silver. Sterling silver contains mostly silver and another metal which increases its overall strength. After some use and exposure to the sunlight and air, you may find that the silver turns to a yellowish-brown hue, or tarnish. There are several ways to eliminate the tarnish. I like to use a silver-polish cloth that can be found at most department stores. Simply rub the cloth over the tarnished areas and the silver will be brought back to its original shine and color. Making a paste of baking soda and water can also be used. Rub, clean and dry the tarnished areas with this paste will also give one the same result. Several other options are discussed on the internet but these are more time consuming and used for larger objects.