In the silver ore of Laurium lead was largely present, and according to Pliny, the ore was first melted down to the substance called “Stannum,” a union of lead with silver. This was taken to the refining oven, where the silver was separated by heat, and the lead remained half glazed in the form of litharge, which in its turn was reduced. But the ancients were also familiar with the use of quicksilver in the extraction of other metals, and the moderns have only a claim to re-discovery in this respect. The bellows and charcoal were employed to produce the extreme heat required in refining processes. Various substances are mentioned as the products of these ancient metallic operations; the “flower” of gold and of copper; the “foam” of silver, with some others, all of which were used in medicine. In the mines of Laurium, copper, cinnabar, and “sil,” a lightish yellow earth much used by painters, and containing iron, were also found. But though Greece had mines of silver and even of gold, still great part of the precious metals in circulation was imported from Asia and Africa. India, the great source of wealth and luxury in all times, furnished copious supplies for those large deposits of bullion stored in the temples and treasuries of Greece. A very natural transition leads us to the Greek and Roman coinage. Silver money was first coined at Ægina, so early as 869 B. C., and was originally the only current coin in Greece. The early coins are rather rough in appearance, and bear a rude mark on the reverse, as if from a puncheon on which the metal was placed for striking the piece. The Athenian silver money was remarkably pure, indeed so much so as to be taken at a premium throughout Greece. Some coins contained only one-sixtieth part of their weight in baser metal, whilst our own silver coinage contains a twelfth. Among the Greeks, gold coinage was subsequent to silver, and bronze was still later introduced. The earliest Roman coins were composed of bronze, and were cast in a mould instead of being struck as in Greece. Some remains of Roman coinage show the cut edge of the line of metal which united adjacent coins when taken from the mould, in which the whole row had been cast together; and some such rows are still found in an undivided state. The cumbrous nature of the early Roman coinage was such that each piece weighed a pound. In fact, in this respect it seemed to come near the weighty iron coinage of Sparta, of which we may add that no remains exist.