as, sixteen to sestertius, and sixty four to a denarius. I have a site on that denomination: http://augustuscoins.com/ed/quadrans/ However, if we include products of Rome stuck for distribution in the east, there is a still smaller denomination. We are not certain what it was called then. Several names for the denomination have been proposed: "uncia," "semis," [I don't think it is a semis], "chalkous," and "half-quadrans." Trajan. 12 mm. 1.02 grams. Very small. Struck from Roman mint dies for distribution in Syria RPC III 3681 Antioch, chalkous RIC II Trajan 443 "semis" page 276 "Probably 101-103" McAlee, Antioch, 526 "rare" page 214 "half-quadrans/chalous" Sear II 3250 "copper uncia" To give you a better feeling for its size, here it is compared to a 19 mm US cent. Of course, there are small very late Roman AE4s, but this type is more than two centuries earlier. Show us some small Roman coins!