Real silver can indeed tarnish over time. This common phenomenon is a natural chemical process that affects the metal’s surface. Tarnish appears as a discoloration, often starting as a dullness or yellowish tint before progressing to darker shades like brown or black. Tarnishing does not indicate poor quality silver; instead, it is a normal reaction of the metal to its environment.
Understanding Silver Tarnish
Silver tarnishing occurs primarily due to a chemical reaction between silver and sulfur compounds present in the air. The most common culprit is hydrogen sulfide, a gas found in trace amounts in the atmosphere, often with a faint “rotten egg” smell. When silver comes into contact with these sulfur-containing substances, it forms a thin layer of silver sulfide (Ag₂S) on its surface. This silver sulfide is a black crystalline compound, which is what we observe as tarnish.
The speed at which silver tarnishes can be influenced by several environmental factors. High humidity accelerates the reaction, as moisture in the air helps facilitate the chemical exchange. Air pollution, certain foods like eggs and onions, and even rubber products contain sulfur compounds that can contribute to tarnishing. Oils and sweat from human skin, along with residues from personal care products such as lotions and perfumes, can also speed up the process. While pure silver is less prone to tarnishing, it is typically too soft for practical use; most silver items, like sterling silver (which is 92.5% silver and 7.5% copper), include other metals that can also react with environmental elements.
Proactive Steps to Prevent Tarnish
Protecting silver from tarnishing involves minimizing its exposure to reactive elements. Proper storage is a highly effective method; keeping silver in airtight containers or bags can significantly reduce contact with sulfur compounds in the air. Anti-tarnish strips or cloths, often made of flannel or specially treated fabric, provide an additional layer of protection by absorbing airborne sulfur. Storing silver in cool, dry conditions and away from high humidity also helps. Small packets of desiccant crystals or even a piece of chalk can absorb moisture in storage areas.
Careful handling also contributes to preventing tarnish. Wearing cotton gloves when handling silver can prevent the transfer of oils, salts, and acids from your skin, which can accelerate tarnishing. Remove silver jewelry before applying lotions, perfumes, or hairspray, and before exposure to cleaning chemicals or chlorinated water. Regular, gentle cleaning with a soft cloth to remove any accumulated dirt or oils before tarnish has a chance to form can also help maintain its shine.
Restoring Silver’s Shine
When silver has already tarnished, various methods can effectively restore its luster. Commercial silver polishes and polishing cloths safely remove the silver sulfide layer without damaging the underlying metal. These products often contain mild abrasives or chemical agents that gently lift away tarnish. When using a polishing cloth, it is helpful to rub gently in small circular motions, turning the cloth frequently to use a clean section.
A home remedy for removing tarnish involves a chemical reaction using baking soda and aluminum foil. This method works on the principle of an electrolytic reaction, where the silver sulfide tarnish is converted back into silver, and the sulfur transfers to the aluminum foil.
To perform this, line a heat-resistant dish with aluminum foil (shiny side up), place the tarnished silver on the foil, add a few tablespoons of baking soda, and pour hot water over the items to submerge them completely. The tarnish will typically begin to disappear within minutes, and the silver can then be rinsed and dried thoroughly with a soft cloth. Avoid abrasive materials like toothpaste, as they can scratch the silver’s surface. Be cautious with harsh chemicals or this method on items with gemstones or plating. For heavily tarnished pieces or delicate antiques, consult a professional silver cleaner.