Georgian coins
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These two coins are both halfpennies, and although it's hard to be sure with coins found in this worn and corroded condition, they probably date to the 1770s and the reign of George III (his portrait is faintly discernable).
The right-hand coin has been cleaned using a vinegar-based (acid) solution, which has stripped away the surface layer and exposed bare metal - giving it a characteristic brightness. This home experiment was, thankfully, only performed after the coin had been identified and deemed expendable. This sort of chemical cleaning is essentially destructive and drastically reduces the value of artefacts - both in terms of archaeological evidence as well as financially (a valuable coin may be ruined and made worthless by such well-meant efforts). The cleaning and conservation of metal objects is a delicate art, and professionals spend a long time learning how to do it without damaging the artefacts. If in doubt, leave it dirty - and safe.
Material: metal
Period: Post Medieval
Find spot: Eastwood Farm, Brislington, ST 6371
Exhibit contributed by Dave Setter & Rod Webb
Text written by Ken Taylor, 2012
Photographer: Ken Taylor
Acquisition number: 120224a4