Electrum

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Electrum is a naturally occurring alloy of gold and silver, with trace amounts of copper and other metals. Colour ranges from pale to bright yellow, depending on the proportions of gold and silver. Gold content of naturally-occurring electrum in modern Western Anatolia ranges from 70% to 90% in contrast to the 45-55% of electrum used in ancient Lydian coinage of the same geographical area.[1]

Electrum was used as early as the third millennium BC in Old Kingdom Egypt, sometimes as an exterior coating to the pyramidions atop ancient Egyptian pyramids and obelisks.

Electrum was also used in the making of ancient drinking vessels and coins.

Composition

Electrum consists primarily of gold and silver but is sometimes found with traces of copper and other metals. As a result, electrum is usually a good conductor of electricity.

Analysis of the electrum composition in ancient Greek coinage dating from 600 BC showed that the gold composition was 55.5% in archaic Phocaea. In the early classical period, the gold composition of electrum ranged from 46% in Phokaia to 43% in Mytilene. In later coinage from these areas, dating to 326 BC, the gold composition averaged 40% to 41%.

Appearance

The color of electrum is pale yellow or yellowish-white and the name is a Latinized form of the Greek word ηλεκτρον (elektron) mentioned in the Odyssey meaning a metallic substance consisting of gold alloyed with silver. The same word was also used for the substance amber, probably because of the pale yellow color of certain varieties, and it is from the electrostatic properties of amber that the modern English words "electron" and "electricity" derive.

Electrum was often referred to as white gold in ancient times but could be more accurately described as "pale gold". The modern use of the term white gold usually concerns gold, silver and palladium alloys.

History

Electrum is mentioned in an expedition sent by Pharaoh Sahure of the Fifth dynasty of Egypt (see Sahure).

Electrum is referred to three times in the Bible. In all three instances it is used to describe a type of glow seen by the prophet Ezekiel in visions (Ezekiel Ch.1 Vs.4 and 27;Ch. 8 Vs. 2)

Electrum is believed to have been used in coins circa 600 BC in Lydia under the reign of Alyattes II.

Electrum was much better for coinage than gold, mostly because it was harder and more durable, but also because techniques for refining gold were not widespread at the time. The discrepancy between gold content of electrum from modern Western Anatolia (70-90%) and ancient Lydian coinage (45-55%) suggests that the Lydians had already solved the refining technology for silver and were adding refined silver to the local native electrum some decades before introducing the pure silver coins cited below.

In Lydia, 14.1 grams of electrum was made into one stater (meaning "Standard"). A stater was about one month's pay for a soldier. To complement the stater, fractions were made: the trite (third), the hekte (sixth), and so forth, including 1/24 of a stater, and even down to 1/48th and 1/96th of a stater. The 1/96 stater was only about 0.14 to 0.15 grams.

Because of the variety of electrum's composition, it was rather difficult to determine the exact worth of each coin. Widespread trading was somewhat hampered by this, as a foreign merchant would offer rather poor rates on local electrum coin.

These difficulties were eliminated in 570 BC when pure silver coins were introduced. However, electrum currency remained fairly popular until approximately 350 BC. The simplest reasoning for this would be that, because of the gold content, one 14.1 gram stater would be worth as much as ten 14.1 gram silver pieces.