"Sestertius", purported date A.D. 69.

Obv. Otho, bareheaded, draped.
IMP.OTHO CAESAR AVG.TRI.POT.

Rev. Emperor clasps hands with one of three legionaries carrying standards; trophy(?).
SECVRITAS P.R.S.C.

Unfortunately, all surviving coins of the hapless Otho - he suicided 16 April, 69, after a reign of three months - are either gold or silver. For whatever reason, the Senate minted no bronze coins in his name. Yet Otho had set great store on having the support of the Senate. Perhaps there was no shortage of bronze coins at the time of his accession. Perhaps Otho hesitated to impose on the Senate a duty which he knew it would have found distasteful.

Be that as it may, this is the kind of bronze coin which would undoubtedly have met with Otho's approval. The portrait is a fine one, consistent with those on his precious metal coins. For the reference to Securitas in the reverse legend we may compare coin 70, depicting Securitas herself, holding a wreath and a sceptre. In an era notorious for its political instability, such a reverse provides a striking example of wishful thinking.

The coin underwent an electron probe in the Department of Mining and Metallurgical Engineering. This involved putting it in a high vacuum, bombarding it with electrons and analysing the electrons received in turn from its surface.

As a result we know that its fabric is a copper-silver alloy, with small quantities of nickel, zinc and lead added. There is clear evidence of "preferential crystallisation": the proportions of copper and silver vary in different parts of the coin. Above all, it is very likely an ancient forgery and definitely not a recent one.