In 1971, the Arbeia Roman Fort and Museum in South Shields, England, had on display what was thought to be an ancient sestertius coin; what did the coin actually turn out to be, and who identified it as such?

THE LEAST ACCURATELY LABELLED MUSEUM EXHIBIT
A first-class example of inaccurate labelling was discovered in October 1971 in County Durham. The object was exhibited in a South Shields museum as a Roman sestertius coin, minted between AD 135 and AD 138. However, Miss Fiona Gordon, aged 9, pointed out that it was, in fact, a plastic token given away free by a soft drinks firm in exchange for bottle labels. The dating was, in her view, almost 2,000 years out.
When challenged to provide evidence, she said: 'I knew because the firm's trademark was printed on the back.'
A spokesman for the Roman Fort museum said: 'The token was designed as a Roman replica. The trouble was that we construed the letter "R" on the coin to mean "Roma". In fact it stood for "Robinsons", the soft drink manufacturers.'
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