Achaemenid coinage

The coinage of the Achaemenid Empire was a continuation of the coins of Lydia. Coins were issued from 520 BCE-450 BCE to 330 BCE for the Daric and Siglos. It seems that before then, a continuation of Lydian coinage under Persian rule was highly likely . Achaemenid coinage includes the official imperial issues (Darics and Sigloi), as well as coins issued by the Achaemenid governors (Satraps), such as those stationed in ancient Asia Minor.

Daric

Darius first introduced a reformed currency system at about 520-480, the precise period is debatable. The rate of exchange was 1 Daric = 20 Siglos. It consisted of a Daric of between 8.10-8.50 grams in weight and based on the Babylonian shekel of 8.33 grams. The purity was between 98-99% gold.

After the capture of Babylon by Alexander, the Satrap Mazaeus issued the double Daric of 16.65 grams in weight whose image was based on the Daric coin and bore his name until his death in 328 BCE. 1 Daric = 25 Attic Drachmae.

Siglos

Siglos is 5.40-5.60 grams each, but is based on the 0.5 Lydian Siglos of 10.73-10.92 grams for the full unit. Purity was at first issue 97-98% but by the middle 4th century was 94-95%. 1 Siglos = 7.5 Attic Obols