Those coins above are very common. However, during the reign of Basil II in 976-1025 the follis became bigger and heavier: Anyone here who collects Byzantines knows that the follis of 800s and 900s are smaller and leighter in comparision with that annonymous of Basil II. I want to ask: Do we know whether the bigger and heavier follis of Basil II had more value or purchasing power than the previous ones from 800s and 900s? I can see that for 15 follis you could buy 1 silver miliaresion if my mind serves me right. But does 15 follis of Basil the Macedonian (the first coin) have the same value as 15 follis of Basil II (the last coin)? The latter one is bigger and heavier as you know. Thank you for any help you can provide. Peace.