The Ancient History of Copper
Copper was one of the first metals to be used by humans. The main reason for its early discovery and use is that copper can naturally occur in relatively pure forms.
Although various copper tools and decorative items dating back as early as 9000 BCE have been discovered, archaeological evidence suggests that it was the early Mesopotamians who, around 5000 to 6000 years ago, were the first to fully harness the ability to extract and work with copper.
Lacking modern knowledge of metallurgy, early societies, including the Mesopotamians, Egyptians, and Native Americans, prized the metal mostly for its aesthetic qualities, using it like gold and silver for producing decorative items and ornaments.
The earliest time periods of organized production and use of copper in different societies have been roughly dated as:
Mesopotamia, circa 4500 BCE
Egypt, circa 3500 BCE
China, circa 2800 BCE
Central America, circa 600 CE
West Africa, circa 900 CE
The Copper and Bronze Ages
Researchers now believe that copper came of regular use for a period—referred to as the Copper Age—prior to its substitution by bronze. The substitution of copper for bronze occurred between 3500 to 2500 BCE in West Asia and Europe, ushering in the Bronze Age.
Pure copper suffers from its softness, making it ineffective as a weapon and tool. But early metallurgy experimentation by the Mesopotamians resulted in a solution to this problem: bronze. An alloy of copper and tin, bronze was not only harder but could also be treated by forging (shaping and hardening through hammering) and casting (poured and molded as a liquid).
The ability to extract copper from ore bodies was well-developed by 3000 BCE and critical to the growing use of copper and copper alloys. Lake Van, in present-day Armenia, was the most likely source of copper ore for Mesopotamian metalsmiths, who used the metal to produce pots, trays, saucers, and drinking vessels. Tools made of bronze and other copper alloys, including chisels, razors, harpoons, arrows, and spearheads, have been discovered that date to the third millennium BCE.
A chemical analysis of bronze and related alloys from the region indicates that they contained approximately 87 percent copper, 10 to 11 percent tin, and small amounts of iron, nickel, lead, arsenic, and antimony.
Copper in Egypt
In Egypt, the use of copper was developing around the same period, although there is nothing to suggest any direct knowledge transfer between the two civilizations. Copper tubes for conveying water were used in the Temple of King Sa’Hu-Re in Abusir that was built around 2750 BCE. These tubes were produced from thin copper sheets to a diameter of 2.95 inches, while the pipeline was nearly 328 feet in length.
The Egyptians also used copper and bronze for mirrors, razors, instruments, weights, and balances, as well as the obelisks and adornments on temples.
According to biblical references, massive bronze pillars, measuring 6 feet in diameter and 25 feet tall once stood on the porch of King Solomon’s Temple in Jerusalem (circa ninth century BCE). The interior of the temple, meanwhile, is recorded as containing the so-called Brazen Sea, a 16,000-gallon bronze tank held aloft by 12 cast bronze bulls. New research suggests that copper for use in King Solomon’s temple could have come from Khirbat en-Nahas in modern-day Jordan.
Copper in the Near East
Copper and, in particular, bronze items spread throughout the Near East, and pieces from this period have been uncovered in modern-day Azerbaijan, Greece, Iran, and Turkey.
By the second millennium BCE, bronze items were also being produced in large quantities in areas of China. Bronze castings found in and around what are now the provinces of Henan and Shaanxi are considered to be the earliest use of the metal in China, although some copper and bronze artifacts used by the Majiayao in eastern Gansu, eastern Qinghai, and northern Sichuan provinces have been dated as early as 3000 BCE.
Literature from the era shows how well-developed Chinese metallurgy was, with detailed discussions of the exact proportion of copper and tin used to produce different alloy grades used for casting different items, including cauldrons, bells, axes, spears, swords, arrows, and mirrors.
Iron and the End of the Bronze Age
While the development of iron smelting put an end to the Bronze Age, the use of copper and bronze did not stop. In fact, the Romans expanded their uses for, and extraction of, copper. The Romans’ engineering ability led to new systematic extraction methods that particularly focused on gold, silver, copper, tin, and lead.
Previously local copper mines in Spain and Asia Minor began to serve Rome, and, as the empire’s reach broadened, more mines were integrated into this system. At its peak, Rome was mining copper as far north as Anglesey, in modern-day Wales; as far east as Mysia, in modern Turkey; and as far west as the Rio Tinto in Spain and could produce up to 15,000 tons of refined copper a year.
Part of the demand for copper came from coinage, which had begun when Greco-Bactrian kings issued the first copper-containing coins around the third century BCE. An early form of cupronickel, a copper-nickel alloy, was used in the first coins, but the earliest Roman coins were made of cast bronze bricks adorned with the image of an ox.
It is believed that brass, an alloy of copper and zinc, was first developed around this time (circa the third century BCE), while its first use in widely circulated coinage was in Rome’s dupondii, which were produced and circulated between 23 BCE and 200 CE.
It is not surprising that the Romans, given their extensive water systems and engineering ability, made frequent use of copper and bronze in plumbing-related fittings, including tubing, valves, and pumps. The Romans also used copper and bronze in armor, helmets, swords, and spears, as well as decorative items, including brooches, musical instruments, ornaments, and art. While the production of weapons would later shift to iron, decorative and ceremonial items continued to be made from copper, bronze, and brass.
As Chinese metallurgy led to different grades of bronze, so did Roman metallurgy develop new and varying grades of brass alloys that had varying ratios of copper and zinc for particular applications.
One legacy from the Roman era is the English word copper. The word is derived from the Latin word cyprium, which appears in early Christian-era Roman writing and was likely derived from the fact that much Roman copper originated in Cyprus.