Our newly published research authenticating coins of the “Roman emperor” Sponsian drew some critical comments in your pages from Richard Abdy at the British Museum (Coins study suggests ‘fake emperor’ was real, say scientists, 23 November).
Abdy seems to be suggesting that it is somehow circular for us to say that the coins demonstrate the existence of an emperor Sponsian, but that it was Sponsian who made the coins. These statements are complementary, not circular. Without intending to draw any absurd comparison, Tutankhamun was originally known only from hieroglyphs on rare objects, but then they found the body.
Rather than going “full fantasy”, our hypothesis for the historical Sponsian as a commander in Dacia (Roman Transylvania) during the declining days of imperial power is based on evidence from the coins themselves and their provenance. It helps explain the paradox that they appear deeply worn – and therefore were in circulation – and yet are extremely rare and known only from that area. We have put all our peer-reviewed research in the public domain, including more than 100 pages of technical reports from the scientific team on the composition of the metal, the patterns of wear, and the nature of the earthen deposits on the surface.
We now look forward to engaging constructively with the experts at the British Museum and elsewhere in debating this evidence.
Prof Paul Pearson
University College London
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