Gold and Silver are the two most commonly used precious metals. Gold was a very popuear substance for use in ancient jewelry for three important reasons:
1. It Could Be Found Occuring Naturally in a Pure of State
2. It Was Easily Worked
3. It Did Not Corrode
Gold in the form of nuggets is found in river beds mixed with quarts, from which it is separated by washing or panning. It also exists as a mineral mixed with silver and copper. Initially these natural alloys were used to make pure gold. The name given to the alloy in which silver occurs with gold in a ratio of 1 to 5 is white gold or electrum. Archaeological evidence suggests that gold was first refined in Anatolia in Turkey. An idea of how old the origins of this process might be, is provided by the Greek word “obryza”. This word derives from Hittite and indicades ” melting.” Pactolos river was a major source of gold in antiquity. This has been confirmed by the excavations at the Lydian capital, Sardis, which have revealed traces of early furnaces beside the Pactolos, used for refining gold.
If gold is found in association with silver, the ore is put into a porous earthenware crucible and lead is added in order to get the two metals separate. The crucible is then heated over a charcoal fire in order to make the ore molten. This process is knows as cupellation. The pure molten gold is made into ingots by pouring it out into stone moulds. Goldsmiths would hammer these ingots into gold sheets, from which they would then make individudal pieces of jewelry. If it was desirable to make thinner sheets of gold, they would be placed between strips of stout leather or ebony wood and then hammered or beaten to the required thickness. Another process used for separating gold and silver from naturally occuring electrum is called cementation. This involves making the electrum into slab-shalped blocks and sprinkling over them a mixture of brick dust ans alt. The blocks and mixture are places, one layer on top of another, inside a coarseware cooking vessel and heated to a temperature of 700-800 C. It is then left in this red-hot state for some time, causing the silver to become attached to the brick dust and the gold to be thus released. The contencts of the cooking vessel are emptied out once this process is complete, and the gold is collected. Another process, knows as empellation, is then used to separate out the silver. Silver, like gold, is a precious metal that is frequently used in jewelry manufacture. It is usually found naturally in an alloy called Galena made up of a mixture of lead and silver. Refining silver from this alloy was first achieved in Anatolia in the 3rd millennium BC. The ore is first crushed, then washed and sifted. The refining of gold also produces quantities of silver and as with gold, refined silver would be made into ingots for further use.
Resource: Museum of Anatolian Civilizations, Ancient Jewelry