NOT IN RIC
UNLISTED ISSUE. Not attested in RIC. These enigmatic uniface gold pieces are often pierced or mounted with a loop. They were sometimes described as 'Indian imitations' from later period but modern scholars regard them as official products.
According to Depeyrot, who also made a brief catalogue of them, they were not money but were struck at some western mints as military donatives (Georges Depeyrot, "Les médaillons d’or unifaces du quatrième siècle (318–340)", Italiam fato profugi hesperinaque venerunt litora. Numismatic Studies dedicated to Vladimir and Elvira Eliza Clain-Stefanelli, ed. T. Hackens, Louvain-la-Neuve 1996, p. 165: "[...] ces objets ont été préparés pour des distributions liées aux divers donativa lors des campagnes militaires").
According to Holmes, they were "military merit awards of some sort - badges of status of recognition of achievement or valour" (N.M.McQ. Holmes, "A Uniface Gold Medallion of Constantine II", Numismatic Chronicle 2004, p. 235).
Recently, Bland confirmed "that these medallions were not struck as currency but to be worn". However, he also suggested that "they may have been produced (a) as subsidies for the barbarians [...], or (b) as payment for troops of barbarian origin," because a significant number of these pieces "were found in the barbaricum" (Roger Bland, "Gold for the Barbarians? Uniface Gold Medallions of the House of Constantine Found in Britain and Ireland", Britannia, vol. 43, November 2012, p. 222).
Listed in Depeyrot's paper (p. 169, no. 17).