Gold in a pure state is found in the form of particles and nuggets (native gold) in goldfields and alluviums. As such it can be used without further treatment. There are also gold ores, such as pyrite and quartz, that include gold in seams or veins. This kind of gold has different quantities of other metals - such as silver and copper - and therefore has to be refined. One of the oldest ways to purify gold is by cupellation.
The most important gold deposits of the Greek and Roman world were on Mount Pangaion (Thrace), on the island of Siphnos (Cyclades), and in Lydia, Nubia, Spain, and Gaul. In Italy the Romans extracted gold in the territory of the Salassi - a Celtic population located in what is nowadays the area around Ivrea and along the Dora Baltea River.
Military conquest was another important source of this precious metal: as an example, in 167 B.C. Lucius Aemilius Paullus's victory over Perseus of Macedon yielded more than 5 and a half tons of gold, in addition to an even higher quantity of silver, for a total amount of more than 83 tons of precious metals, coined and not. Gold and silver also reached the State's treasury from tolls and the collection of taxes.
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