The invention was soon extended to pure gold and silver, and there is good reason to believe that by the time of Croesus (568-554 B.C.) both these metals were used for purposes of coinage in Lydia.
The Greeks begin to coin money.
The clever Greeks of Asia Minor, who formed the portal through which so many of the arts of the East reached the Western lands, were not slow to adopt, and by reason of their superior artistic taste to improve, the great Lydian invention. To the Ionic cities such as Phocaea and Miletus we must probably ascribe the credit of substituting artistically engraved dies for the rude Lydian punch-marks, and at a somewhat later period of inscribing them with the name or rather the initial of the people or potentate by whom they were issued.
The official stamps by which the earliest electrum staters were distinguished from mere ingots consisted at first only of the impress of rude unengraved punches, between which the lump or oval-shaped bullet of metal was placed to receive the blow of the hammer. Subsequently the art of the engraver was called in to adorn the lower of the two dies, which was always that of the face or obverse of the coin, with the symbol of the local divinity under whose auspices the currency was issued.
As our object is to deal with coins from the point of view of metrology, the short summary here given of the genesis of the art of coining will suffice for our purposes.
Weight standards.
“Silver was very rarely at this early period weighed by the same talent and mina as gold, but, according to a standard derived from the gold weight, somewhat as follows:—
Gold was to silver as 13·3:1. This proportion made it difficult to weigh both metals on the same standard. That a round number of silver shekels or staters might equal a gold shekel or stater, the weight of the silver shekel was either raised above or lowered below that of the gold. The heavy gold shekel weighed 260 grains Troy, being the double of the light gold shekel, which weighed 130 grains Troy (8·4 grammes).