Why Does Mexican Silver Tarnish?

Silver items tarnish if not properly maintained.

Unfortunately, all silver tarnishes through a chemical reaction with the air, not just Mexican varieties. Handcrafted silver items, some of which are traditionally made in Mexico, tend not to have treatments sometimes applied to commercial products or are made of purer silver that is more susceptible to reactions. All silver will eventually tarnish if not properly maintained; fortunately, a few simple steps can go a long way in maintaining and restoring silver.

The Process

The black spots and lines that develop on silver and are usually referred to as "tarnish" are actually the result of a chemical reaction between silver and the sulfur in the air, forming streaks of silver sulfide. Sulfur is the result of organic combustion processes such as the burning of fossil fuels and is present, in small amounts, in the entire atmosphere. Sulfur can also appear in larger concentrations around combustion engines or coal-burning stoves.

Polishing Through Use

While conventional wisdom seems to be that storing your silver away will prevent tarnish, frequent use will actually help silver stay polished. Repeated use and washing and drying keeps acidic foods like tomatoes or coffee from settling on your silverware and causing discoloration and tarnishing. Some foods, such as eggs, even contain sulfur and will accelerate the tarnishing process.

Chemical Polishing

Several chemical polishes and dips are also available to keep silver shining and remove tarnishing.

Polishes tend to have abrasive elements that slowly scratch away the silver sulfide and leave the silver underneath the tarnish looking as shiny as you would expect from new silver. Polishes also usually contain harsh chemicals like ammonia to dissolve silver sulfide and chemical elements to delay future tarnishing.

Simply dipping the silver in a chemical dip is an easier process than using a polish, but dips contain very toxic chemicals to restore the silver. Rather than removing tarnished silver, dips restore silver by targeting and removing the sulfur.

Caution with Silver-Plated Pieces

Much like pure silver pieces, silver-plated pieces will also tarnish as the surface silver comes into contact with the air. Unlike pure silver, however, repeated polishing will eventually remove the entire silver surface layer and expose the base metal. Thus, in the case of silver-plated items, use non-abrasive tarnish-removal methods, such as a dip, to keep the silver clean.

Baking Soda Cleaning

A very effective and more environmentally friendly way of cleaning silver, baking soda dissolved in boiling water easily removes tarnish.

Simply bring water to a boil in an aluminum pot or a pot with aluminum foil covering the inside and dissolve a quarter cup of baking soda in the water. Dip silver pieces in the froth and dry to remove tarnish, repeating the process as many times as necessary to completely remove tarnish. This process can be used to keep silver-plated pieces intact and will keep you and the environment from exposure to dangerous chemicals.

References

• Blitz, Inc.: Why Silver Tarnishes
• Bella Online: The Unlikely Power of Baking soda
• EcoCycle: Alternative Cleaners and Recipes