Mines, ancient silver, 16 copper

Here is a typical example of a relevant problem an ancient Sardinian hillside mine. The island of Sardinia has been mined for silver, zinc, copper, and lead since Phoenician and Roman times and, until the 1970s, was the largest source of heavy metals in Europe. It has left a legacy of pollution problems associated with mine drainage, carrying pollutants from hillside mines down to valleys below. This is a situation that could well be applicable to treatment by an electrokinetic barrier. The application is as shown in Figure 16.1. 

This word chrysocolla of the ancients, which denotes malachite, was not confined to that mineral, as appears particularly from the extended description of Pliny. He mentions the substance dug from the mines in proximity to gold, but he also states that it is a liquid found in the shafts of mines—a slime hardened by the cold of winter till it haB the hardness of pumice. The most valued is from copper mines, the next best from silver mines, and that from the gold mines is inferior. In the mines also an artificial chrysocolla is made by allowing water to percolate into the veins during the winter and spring, and evaporating these in July and August. 

Apart from direct studies of ancient mining or metallurgical remains, extensive fieldwork is needed also to establish the lead isotope characteristics of copper and lead-silver deposits that could have, or are known to have been, worked in the Bronze Age. In the past 8 years we have explored ore deposits in Greece, Cyprus, Sardinia, and the Sinai. 

Material resources often have controlled a nation s rise—and fall. Ancient Egypt developed bronze from its copper and tin, and weapons therefrom enabled it to dominate its sphere when copper ran out, Egypt succumbed. Similarly a silver mine gave Athens this noble metal for trading with its exhaustion Athens deteriorated. Energy resources today are equally important to national attainments, although the world s economics and politics now are very much more complicated than those of the ancients. 

Copper (Cu) is believed to have been mined for 5,000 years. Silver (Ag) has been known since ancient times. Pure Ag has a brilliant metallic luster. It is used in mirror production and deposited on glass or metals by various methods, such as chemical deposition and vacuum evaporation. Gold (Au) is known and highly valued from earliest times. It is found in nature as the free metal. It is inert and a good reflector of infrared. Ag and Au are noble metals while Cu is a non-noble metal. Table 2.7 summarizes some physical properties of group-Ib metals. 

Strabo (63 B.C. - 24 A.D.) writes about mines within the Roman world in his Geography. Among the specific t5 es of mines mentioned were iron, copper, arsenic, gold, silver, lead, tin and emerald, but not a word about sulfur mines. He goes on to report that all sorts of mines existed in Italy (6.4.1), and of ancient copper mines at Temesa, in south-western Italy, near Sicily (6.1.5 12.3.23). No mining in Sicily itself was reported. 

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