For those readers who (like me) found the Roma explanation of the description of the Attalus medallion as “24 siliquae” less than clear I offer my take on the question. Firstly, note that “siliqua” can have three different meanings in this context: Firstly, it can designate the “reduced siliqua”, a silver coin of Constantius II weighing 2 scripula (= 1/144 libra = 2.27g) - the name in this case is of course modern. Secondly it can mean the “siliqua of account”, a purely accounting term meaning 1/24 of the value of one gold solidus. The solidus weighs (nominally) 1/72 of a pound = 4 scripula = 4.55g. Thirdly, it can also mean the Roman carat, a small weight unit of 1/6 of a scripulum (= 1/24 of a solidus) = 0.189g As to the value of the medallion, if we assume that it was meant to weigh ¼ of a libra (c. 82g), then taking the gold/silver value ratio as 18 the medallion is worth ¼ x 1/18 = 1/72 of a libra of gold, i.e, one solidus of gold, or 24 siliquae of account. E voila – the 24 siliquae medallion. Ross G.