Weights and Purity
Although the currency we use today in the United States is no longer backed up with gold or silver, money in ancient times was valued based on the content and purity of its metal as well as its weight. Because coins were originally made of only silver and gold, they were often small in size; hence the phrase “small change” had a double meaning—it was small both in value and in size, some even small enough to fit through the eyelet in a shoe.5 (pp. 37)
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The above are the obverse and reverse of a tiny Yehud coin from Israel, 8 mm in diameter and 0.4 g in weight, http://www.vcoins.com/trionfo/store/viewItem.asp?idProduct=245&large=1 |
Furthermore, many coins were made of an amalgam of silver and gold called electrum, whose color depended on its relative gold and silver content.
Lydian electrum coin dating from 650-600 B.C.E., from modern day Turkey http://www.thebritishmuseum.ac.uk/cm/k127625.jpg |
Because darker yellow coins contained more gold, they were worth more, a very befuddling concept when one considers that coins of many shades of gold all circulated together. Because shades of a color can be so subjectively interpreted, arguments about the values of coins grew rampant.5 (pp. 37-45) |
Because of the inherent worth of their currency, ancient peoples always looked for ways to cheat the system. The edges of some coins display chisel marks, cut by ancient people who were checking for authenticity of the metal. Such marks were on the look out for ancient forgeries, which consisted of cheaper metals plated with either gold or silver. Sometimes, bronze coins would be coated with a mixture of ground up silver or gold and mercury. When heated, the metals would melt over the surface of the coin and the mercury would evaporate, leaving a thin layer of gold or silver behind.5 (pp. 37-45)
Julia Domna silver over copper denarius (193-196 AD) 2.2g (chipped) http://dougsmith.ancients.info/4jdbarb.jpg |
In some instances, however, defects in the coins edges could be attributed to the fraudulent practice of shaving small amounts off of each coin. By collecting such shavings from many coins and melting them together, the unscrupulous could accumulate the equivalent of free money. The only way to protect against this was to weigh coins with each use, which merchants took to doing when they suspected that some coins were lighter than they should have been.5 (pp.37-45)