Many amateur coin collectors are enthralled by the pristine look of coins recently released by the mint. Shiny and perfect they are certainly eye catching. Many coin collectors though appreciate the aesthetic beauty and the authenticity of a toned or tarnished coin. Toning is something that happens naturally to many coins, especially silver ones, and changes the whole look of a coin.
-What is Silver Coin Toning?
Silver toning is best described as the build up of a film upon the surface of a coin. It is normally considered to be the result of the silver reacting with sulphur in the atmosphere. The result of this reaction creates a visible colour change as light is refracted through the film, and colours can range from yellow, through to magenta, cyan and black. It is in essence the same result as seen when a drop of oil lands in a puddle of water.
There are a number of different toning effects that can occur on silver coins, and many collectors seek out bullet toning, the silver toning which changes from the edge of the coin through to its centre, or rainbow toning, toning that consists of multiple colours.
-Why Tone a Silver Coin?
Coin collectors normally fall into two broad types, ones who like pristine coins, those that look like they have just been minted, and those that like coins that show their age. In some case a toned silver coin can be worth more than a pristine one, although this is a rare occurrence. The main reason why silver coins are artificially tones is to cover up a problem with the underlying coin, for example the presence of wear or hairlines.
-How to Tone a Silver Coin
Coins naturally tone, but some dealers and collectors like to artificially tone silver coins. This artificial toning can be a quick fix or a slower process. The slowest method is to let nature do its work. Silver coins left in sunlight and the air will tone, although whether this is artificial can be debated, as it is the same process as real tarnishing. A similar slow process would involve taking a silver coin and placing it in an envelope with a minute amount of sulphur for several years.
For coin collectors and dealers looking for a quicker method then there are many quirky solutions which offer varying degrees of success. Some people will blow cigar or cigarette smoke over their silver coins to artificially increase the presence of sulphur, and a similar method makes use of crushed match-heads for the same reasons. Blow torching silver coins is also another method, as is placing the coin in an oven to bake.
-Identifying Artificially Toned Silver Coins
It is not always easy to know if a coin has been artificially toned or not, although making use of a grading service certainly reduces the risk. The use of match heads or cigar smoke does leave tell tale smells and colour. The most obvious identifier though is the fact that toning occurs over wear or hairlines, this though is by no means conclusive as hairlines could have been caused a century ago, and thus the toning could be natural. It is for this uncertainty that causes many coin collectors to look to pristine rather than the used to build up their collections.