The ancient coinage of Libya comprises two quite distinct aspects. Firstly, in Cyrenaica there is the group of Dorian Greek cities first founded by colonists from Thera in the seventh century B.C., and of these cities we have a fairly continuous range of coins down to Roman times. Secondly, there is the group of Phoenician cities in Tripolitania, whose local coinage has a much more restricted span, covering only the late Roman republic and early empire.
The Cyrenaic coins, like those of most other regions of the Greek world, have a distinctive local character of their own. Among the representations found on these coins we may mention first examples of the flora and fauna of the country including the scorpion, the chameleon, the jerboa, the gazelle. But most typical of all is the silphium plant. This was an umbelliferous plant originally growing wild in Cyrenaica. In early times it formed one of the chief sources of wealth but by the Roman period was becoming extinct, perhaps due to over - exploitation — it has been noted that the plant is depicted less regularly and less realistically on coins even during Hellenistic times. Its nearest modern parallel is considered to be asafoetida, in particular the variety known as Ferula narthex found in Afghanistan. The silphium was valuable for its juice, extracted by an incision of the stem, and was used both medicinally and as a condiment, while the stalk provided vegetable food both for human and animal use. The plant which we see on the coins is depicted with greater or lesser realism showing in detail the leaves with their typical sheath - like bases and the umbels springing outwards; the stem is shown as thick as a tree trunk. But its size is difficult to estimate, and here the coins are not entirely helpful, as sometimes a gazelle is shown lying in front of a tree - sized plant, on others a gazelle seems to peer down at a small bush. But relative scale is not always a strong point with coin designers. In addition to the whole plant as normally shown, separate parts of it are also depicted, especially the heart - shaped fruit. The silphium and its export may during the time of the Battiad dynasty have been a royal monopoly. It used to be thought that on the famous Arkesilas vase we had a picture of the king supervising the weighing and storage of silphium, though more recent opinion favours the view that the commodity in question is bags of wool.