Penniless Billionaires"By A.D. 270, when Aurelian was installed, the economy of Rome was in a bad way. Inflation was soaring. The currency was in chaos, with billions of coins of varying silver and copper content, sizes, weights, and denominations creating confusion. Gradually -- because of the monetary mess -- barter was developing. Dissatisfaction was increasing in the army; the traditional annual salary of 225 denarii, by that time, had been so eroded by inflation as to be almost meaningless. Finally revolts broke out for higher pay. When this was not forthcoming, soldiers demanded a return to payment in commodities. Steadily Roman society was reverting to an agrarian economy and the price of farm produce continued to climb day by day. When the Emperor's representatives tried to work out contracts with the owners of large farms for "victuals at fair prices" the agribusiness interests of that time refused. Finally, the state seized many of the farms from which it expropriated food for its troops.
Aurelian, in an attempt to restore some order in monetary matters, issued two coins to replace the welter of old coins (how he hoped to accomplish this has never been made clear). The smaller coin was tariffed at one denarius and the larger at twenty. But neither contained an iota of silver. They were made entirely of copper and were "washed" during minting in a light, silverlike solution, which gave them a silvery finish.
The 20 denarii piece was similar to our half dollar in appearance and size and was intrinsically as worthless. Two hundred and seventy years before Aurelian had struck the coin 20 denarii of pure silver would have kept a man alive in Rome for almost eight months. In Aurelian's day it would be used up in about a week. The 150 denarii paid yearly to an indigent mother for her dependent child under Nerva's scheme now had the purchasing power of around 3 denarii.
Of course, Aurelian's attempted reform accomplished nothing; it merely abetted inflation. Now that no silver was required in coinage, money roared out of the mints in a greater flood. Prices leaped upward anew as people tried to convert increasingly worthless coins into goods." - Max Shapiro. _The Penniless Billionaires_.