This suggests that one reason for the invention of coinage in that area was to increase the profits from seigniorage by issuing currency with a lower gold content than the commonly circulating metal.Įlectrum 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. The gold content of naturally occurring electrum in modern Western Anatolia ranges from 70% to 90%, in contrast to the 45–55% of gold in electrum used in ancient Lydian coinage of the same geographical area. Its colour ranges from pale to bright yellow, depending on the proportions of gold and silver. The ancient Greeks called it 'gold' or 'white gold', as opposed to 'refined gold'. It has also been produced artificially, and is often known as green gold. Negative charge, is called a positron, or antielectronĮlectrum is a naturally occurring alloy of gold and silver, with trace amounts of copper and other metals. Most other respects, but having a positive instead of a A particle identical to the electron in mass and Through metallic conductors is observed as an electricĬurrent. Previously also referred to asĬorpuscle, an obsolete term. Tubes) as cathode rays and from radioactive substancesĪs the beta rays. Electrons are projected from theĬathode of vacuum tubes (including television picture Which an electron has been detached has a positive chargeĪnd is called a cation. Thus far, no structure has been detected within anĮlectron, and it is probably one of the ultimate compositeĬonstituents of all matter. Electrons are all of one kind, so far as is Practically constant at the lesser speeds, but increasesĭue to relativistic effects as the velocity approaches The electronĬarries (or is) a natural unit of negative electricity,Ĭlassed by physicists as a lepton.
Particles, having a negative charge and about one (Physics & Chem.) one of the fundamental subatomic SeeĪmber also, the alloy of gold and silver, called
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