The History of Mining. Michael Coulson

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СКАЧАТЬ including a basic electric battery which may have been used in the process of treating silver. Some historians even call Asia Minor the Cradle of Civilisation.

      It is therefore not surprising that this region was the centre of a vigorous trading system where Anatolia was the great mining and metal working nation and exported finished metal to its near neighbours. For example, the ancient tin mine at Kestel and the associated smelting site at Goltepe in central Turkey reach back as far as the 3rd millennium BC.

      Copper artefacts have been found all over the broad Asia Minor region; the oldest is thought to be a pendant from the 9th millennium BC found at Shanidar in the Zagros Mountains of north eastern Iraq. Archaeologists have also found copper objects at Cayonu Tepesi in Turkey that have been dated to the 7th millennium BC. Further finds of copper artefacts from the 6th and the 5th millennia BC in Iran and Turkey have also been uncovered. Much of this early copper would have been native, released from rock by weathering over thousands of years. As we have observed in other ancient mining areas, the very earliest use of metals was based on a supply of pure material simply picked up off the ground, a phenomenon that we will come across later in the tale of diamonds in Namibia’s deserts in the 19th century AD.

      A relatively sophisticated trade in copper and copper objects developed over the millennia in the extended area of Asia Minor and the Middle East, and it is quite likely that the growth in this trade put pressure on the supply that was being obtained from native copper findings. Since we are talking about the cradle of technology as well as of civilisation, the response to possible copper supply problems would have been to examine how the pure copper metal had got where it had. Here we are just guessing, but it is likely that very early fossickers saw copper streaks in rock and worked out that these were similar to the native copper that they had been picking up off the ground.

      From here it would have been a matter of developing the processes to extract the copper from the rock. The secret would have been the ability to generate sufficient heat in a rock furnace to melt the copper out of the ore and then separate the two – metal and slag – leaving a relatively pure copper residue. It is believed this smelting technique was developed around the 4th millennium BC.

      One of the most interesting metal mining, smelting and manufacturing sites found in Asia Minor is the Medzamor complex immediately to the east of Turkey in Armenia, which is thought to date back as much as 5000 years. Medzamor was uncovered in the 1960s by Soviet scientists and archaeologists and some western opinion at the time was a little sniffy about its significance. Dozens of smelting furnaces were found and evidence of multiple working of metals covering both copper and other base metals as well as gold. All sorts of metal products were uncovered – including vases, bracelets, rings, spearheads and knives. This suggests a settlement specialising in industrial activities emanating from mining, contrasting with the traditional farming settlements more associated with simple ancient lifestyles.

      Persia, the Empire and Iran

      In the 7th century BC Persia emerged as a major power in the Middle and Near East and in due course its influence extended both east towards India and also further into the Mediterranean, where it often clashed with Greece. Gold was an important factor in Persia’s expansion as it provided the Empire with a legitimate monetary system which supported its political ambitions. Persia’s gold came from both wealth acquired as a result of conquest and from mines which came under its control. This wealth in gold was always useful, as Persia’s major rival at the time, Greece, was rich in the less valuable silver but had limited access to gold. Thus Persia found it was able to buy influence in the eastern Mediterranean without the need for military successes, which was fortunate, as its few sallies forth against the Greeks had singularly failed to achieve anything.

      Persia’s gold came from mines in both Asia and the Middle East, its empire stretching from India and the modern -stans of central Asia, through Iran to the Arabian peninsular. Much of the Empire’s gold was mined as alluvial gold washed down from the mountains of Anatolia (Turkey) in the west and of Bactria (Uzbekistan) in the east. Apart from using gold as currency Persia also kept gold in ingot form as a sort of foreign currency reserve.

      But Persia was a many faceted power. Whilst its interest in gold was of great importance it was also an advanced civilisation with concomitant needs and skills. In the area of metals it embraced the Iron Age earlier than most and quickly built up iron making and working. Hasanlu, a major city in north eastern Iran and now a great archaeological site, was in the 8th century BC a centre for metal working and a pioneer in making iron. Hasanlu was also a crossroads city attracting hosts of invaders throughout the centuries. Importantly for the advance of its technical skills, it also attracted travellers who both brought news of technical developments in mining and metals from foreign parts and took back home news of Hasanlu’s own progress in these industries.

      In the 9th century BC Hasanlu was destroyed by invaders and abandoned, disappearing under rubble and, over the centuries, sand. In the 1950s the city was the subject of archaeological investigation and numerous metal items were found buried, including gold, silver, bronze and iron. A furnace for making iron was also uncovered and numerous well-preserved iron objects including knives, nails, buttons and pots were found. One of the objects, a knife blade, indicated that the ironworkers of Hasanlu had also made progress in making steel, which is harder than iron and thus more suitable for weapons in particular.

      8. The Roman Republic and Empire

      It is in the nature of great empires to expand at least partly because of their need to acquire natural resources to fuel this expansion; one might say that expansion begets expansion, and such wealth as results from this becomes critical to the health of the imperial power. The Roman Republic (510 BC to 44 BC), which saw Rome begin to expand from its primarily central Italian base, and the Roman Empire (44 BC to 476 AD), which continued the expansion, were no exceptions to this. An important economic part of Roman conquests was the acquisition of sources of essential raw materials, in particular metals and minerals. The main areas providing the Empire with key metals were Spain, Britain, France (Gaul), central Europe along the Danube, Greece and Asia Minor. The metals produced included gold, copper, iron, tin and lead.

      The gold mines of Spain were particularly important in providing finance for the Roman Empire as it continued the expansion begun by the Republic. In 31 BC Augustus became Emperor and after military success in subduing Egypt he turned to Spain. Here Rome was already strong in the south and was already exploiting the gold and base metal deposits in the region which had been developed by the Carthaginians before they were ejected by the Romans from southern Spain at the end of the 2nd century BC.

      The Greek geographer, Strabo, in his magnum opus, Geographica, describes in detail the mines of the region that is now Andalucia. The mines in the region produced gold, silver, copper, lead and iron ore, all of which were of course of material value to the Romans. Strabo is particularly interesting on the issue of treatment of the ores, where on occasion furnaces became overheated leading to a loss of metal due to vaporisation. He also describes the necessity for chimneys over silver smelters due to the poisonous nature of the furnace fumes, probably caused by the lead often associated with silver ore. The area was also a source of very high grade ores with pure gold nuggets commonly found on the surface. Copper ore mined was also of a high grade, as much as 25%, but such figures are obviously difficult to authenticate. It is thought that Strabo never visited Spain, his own travels being confined to the eastern end of the Mediterranean, so he relied on third-party sources for his information.

      In the northwest in Galicia, according to Pliny the Elder, the Roman philosopher, naturalist and military commander (see below), gold mining output reached an aggregate figure of over 200,000 ozs. A diversity of mining methods were used, including the traditional alluvial mining techniques along the Spanish run of the Tagus and Douro rivers, and in Galicia larger operations incorporated both underground shaft and gallery mining СКАЧАТЬ