Written by Phillip Berrie
Silver has been known and used since ancient times. In this article we will look at its physical, chemical and biological properties.
Silver has been mined in the Mediterranean and Middle East regions since at least 4000 BCE (Before Common Era) where it was already being refined from lead ores on islands in the Aegean Sea. It is a soft white lustrous metal which has a lot of the characteristics of Gold. It is highly ductile and malleable but it is slightly harder and easier to find than the rarer Gold which makes it popular with jewellers and other craftsman wanting to create usable works of art in metal including cutlery (i.e. Silverware).
Note: Also commonly used in ancient times (as far back as the Old Kingdom of Egypt in 3000 BCE) was the naturally occurring alloy of Gold and Silver called Electrum. More frequently called White Gold these days, this alloy has most of the properties of Gold, but is paler than true gold and uses less of the rarer metal. Electrum was commonly used in early high denomination coins (as far back as 700 BCE) and I mention it here as such coins appear in fantasy fiction and role playing games and I thought readers might be interested in its origin.
A Nugget of Silver; Sourced from Wikimedia Commons
Placed in the Public Domain by 'Minerals of Your World' Project
Silver has many other uses than just being a precious metal. It can be made highly reflective and was used as the reflective layer for glass mirrors as early as 1 CE (Common Era) until the cheaper (though harder to refine) Aluminium replaced it in recent years. And mirrors were just the start of its uses in the field of optics. The first permanent photographic images were produced by Niéphore Niépce and Louis Daguerre in the early 19th century using compounds made from Silver.
Recent trends in colour dyes and digital photography have changed the importance of Silver in photography, but this has not effected the importance of Silver in modern technology. Some of the less obvious physical properties of Silver still make it valuable as a technological mainstay. It is the best electrical conductor found in nature and is also the best metallic conductor of heat known to man. It also finds uses in nuclear physics where, as a metal, its ability to absorb free neutrons makes it suitable for making nuclear control rods for certain types of nuclear reactors.
For me the most fascinating properties of Silver are medicinal. It has a toxic effect on bacteria, viruses, algae and fungi while being non-toxic to higher life forms (Some cultures even use Silverfoil as edible food decoration). Although news to me, this property has apparently been known since ancient times when the Phoenicians kept food stuffs in Silver to prevent spoilage; it kills the microbes that would otherwise break down the organic material. Silver compounds (e.g. Silver Nitrate) were also used widely as antibiotics during the first World War.
Although the use of Silver went out of fashion with the development of Penicillin and other similar antibiotics, its use is being explored again as a broad spectrum antimicrobial because of the rise of the so-called antibiotic resistant super bugs. Strangely enough, this antimicrobial property is enhanced if used in the presence of an electrical field. So it seems to me that there is a lot more uses and things to find out about this strangely alluring metal.
Speaking of which, next time we shall look at Silver's more esoteric uses in both fact and fiction.
References:
The Wikipedia on Silver
http://en.wikipedia.org/wiki/Silver
The Wikipedia on Electrum
http://en.wikipedia.org/wiki/Electrum
The History of metal coated glass mirrors
http://en.wikipedia.org/wiki/Mirror#History
The History of Photography
http://en.wikipedia.org/wiki/Photography#History
N.B. Please note that I although I use the Wikipedia (and WikiMedia Commons) a lot for references, this is for expediency and the familiarity of my readers. Anyone interested in further studies should make use of the references where available and understand that the Wikipedia is a co-operative project contributable to by anyone and must always be looked at in that light.
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