678 metallurgy: Africa AFRICA BY KIRK H BEETZ Almost guaranteed to set a gathering of African archaeologists to arguing is the subject of metallurgy Where it started, how it developed, and how it spread has been disputed in many publications It is possible that the first metal Africans worked was gold, because it often appears as nuggets that can be hammered into shapes Other metals available to Africans were copper, tin, and iron Ancient Africans may have found silver, too, but the archaeological evidence suggests that silver was imported from the Mediterranean world, perhaps from the Iberian Peninsula, the land where Portugal and Spain are today Most archaeologists and historians agree that the smelting of metals in Africa probably began in Egypt The technology for making bronze out of copper and tin probably was imported from the Near East into Egypt When Egypt solidified its control of Nubia, the land south of Egypt, during the reign of Pepy II (r ca 2246–ca 2152 b.c.e.), Africans outside Egypt were still in the Stone Age Is likely that the Egyptians introduced the copper to the Nubians; the Nubians used copper to make spearheads that looked like long leaves, though most of their spears were still tipped with stone Nubian copper tools from that era were either imports from Egypt or copies of Egyptian tools Nubia was rich in gold, and over the years Nubia’s gold mines yielded about 65 pounds of pure gold from about 9,000 tons of ore annually This gold went to enrich Egypt, helping to make Egypt one of the wealthiest nations of the ancient world Elsewhere in Africa gold was being made into jewelry Whether techniques for smelting gold ore were passed from Egypt to Nubians and then to the rest of Africa or Africans figured out these techniques for themselves is unclear That Africans loved the decorative possibilities of gold is plain In central and western Africa people learned to sift gold nuggets out of streambeds and even how to mine gold dust from quartz In the 1600s b.c.e the kingdom of Karmah stretched its dominion northward over lands to the south of Egypt nearly to the first cataract of the Nile River The Karmahn culture was still in the Stone Age and did metalworking Between 1504 and 1492 b.c.e Egypt conquered Karmah and swept south to take control of Nubia Until Egypt’s withdrawal in 1070 b.c.e., Egyptian technology passed to other Africans through Nubia By that time the secrets of making bronze were known to the peoples of northeastern Africa, but they still worked primarily in copper, perhaps because tin was hard to find locally and had to be imported from the north or from western Africa, where there were tin mines The kingdom of Kush arose around 900 b.c.e., encompassing most of the Blue Nile and White Nile rivers During several military campaigns from about 728 to 702 b.c.e Kush conquered Egypt Although ironworking was established in the Near East in the early 1000s b.c.e., Egyptian armies still used bronze weapons, and Kushites used mostly stone weap- ons The use of iron for tools and weapons came crashing in on the Kushites in about 671 b.c.e when Assyria invaded Egypt Although bronze held its edge better than iron, iron was easier to manufacture in large quantities and had special qualities for armor, including its ability to be case-hardened The ancient smiths would either pour liquid iron into molds or hammer it into shape by repeatedly heating it until it was soft, beating it, heating it again, and so on In a bed of carbon, possibly charcoal but more often the ashes of husks of grain, the hot iron would be set to rest This might be done several times, during which the iron would absorb the carbon and harden on the outside while remaining soft and flexible on the inside This meant that when it was struck, iron armor flexed rather than broke Superior tactics and superior armor were the advantages of the Assyrians In 593 b.c.e Kush moved its capital from Napata to Meroë, where iron from mines was plentiful There, a large iron-making industry developed Kushite ironworkers built furnaces out of clay Into these furnaces were inserted clay tubes Bellows, probably made of animal skins, were attached to the outside of the tubes When the bellows were pumped, outside air flowed into and through the furnaces, creating the effect of a blast furnace The superheating caused by the blasts of air allowed the smiths to reach the 2,797 degrees Fahrenheit required to make iron liquid and pourable The smiths could therefore make almost anything they wished out of iron, and although bronze remained the preference for decoration, iron vaulted Kush out of the Stone Age Numerous large slag heaps still exist in Meroë The long-standing African custom of remelting metal objects, especially gold, to be remade into whatever was currently fashionable has made it hard to trace how metallurgy spread Sometime between 700 and 500 b.c.e a major metalworking culture emerged in a valley along the Niger River in western Africa, almost due west of Kush It is called Nok after the village near the tin mine where the first remnants of the culture were found in 1928 Its exceptionally well-sculpted ceramic figures have caught the imaginations of archaeologists, but little is known about the Nok One of the greatest puzzles they present is that they were working metals when Kushites were doing so, and they may have begun smelting iron before the Kush Archaeologists and historians have proposed various ways this could have happened One is that traders brought the knowledge with them from the Phoenicians or the Greeks who traded with the Noks Another is that people fled west from Kush when nomads invaded their kingdom They would have fled along the Sahel corridor, grassy steppes that stretch west to east along the southern edge of the Sahara Another possibility is that the knowledge flowed from tribe to tribe along the Sahel corridor Yet another possibility is that the Nok learned to make bronze and smelt iron on their own In any case, as early as 500 b.c.e the Nok were using blast furnaces of clay with ceramic tubes that may have functioned like the Kushite blast furnaces