silver composition

Silver Composition

Composition of Silver

When silver is formed, it is often combined with other things such as chlorine, sulfur, antimony, or arsenic. This forms various ores from which silver can be refined. It is produced from the electrolytic refining of copper as well as being found in copper, gold, copper-nickel, lead-zinc, and lead ores.

When silver is prepared for the creation of jewelry, it can be left in a mostly pure form (purities of over 99.99% are both possible and available) or it can be refined into sterling silver. When left in its purer forms, silver is not intentionally mixed with anything, and is incredibly soft and malleable. This metal scratches relatively easily since it is so soft, and should only be used for the most “protected” jewelry.

To make silver a little tougher, as well as a great deal less expensive to manufacture and produce, jewelers cut the pure silver with other metals. The most common metal with which silver is combined to create sterling silver is copper. The mix rate is 92.5% silver to 7.5% copper. This is why sterling silver is often stamped with “925” somewhere on the piece, and why it is graded as such.

While there are other grades of silver (such as “Mexican silver” with a 950 grade), none of them are commonly used for jewelry, but rather for larger pieces such as flatware and silver service sets. These can be more or less pure than sterling silver, but rarely does an alloy dip below the 800 mark, meaning 800 parts per 1000 or 80% pure silver. In fact, even this low of a ranking is not often seen outside of specific regions where it is the standard.

The mixture of silver with copper or other metals is actually the cause of the tarnish that you might find on your silver pieces. Silver is very unreactive as a metal, but the alloy known as sterling silver has certain weaknesses to skin oils, atmospheric pollutants, and even common table salt. This causes the silver to tarnish, turning good silver from a bright color to a dull yellow, and then to the dreaded blackish purple shade.

So why mix silver at all? Pure silver does not tarnish easily, however it is very soft and can be scratched and damaged very easily. It is also not good for working into larger pieces since it is so soft. We strengthen the metal with other metals, creating an alloy. There is currently a great deal of activity in the field to find the “perfect” metal with which to alloy silver to create a form of silver that is strong and tarnish resistant, as well as possessing other desirable qualities. Until then, it is sterling for the rest of us.