that he should’. He does, however, give houseroom in Metallica to the opposite view of mining opponents, whose arguments of despoiling and pollution, concerns about the safety of miners and thoughts about the evil products of metals such as weapons of war have a very modern ring. Interestingly many of the mines surveyed by Agricola were located in fairly remote mountainous areas and this led him to believe that their environmental impact was very limited; such a view would not be acceptable today.
Agricola divided Metallica into 12 separate books which covered, amongst other subjects, miners and mining officials, rock strata, mining and surveying, mining equipment, assaying, treatment of both ore and metals (particularly precious metals), management and finance and the manufacture from minerals of basic compounds such as salt and glass. Agricola does not always identify the mines he refers to, perhaps partly because he did that in earlier works such as De Veteribus et Novis Metallis, but he was from Saxony and he does name a number of towns that benefited from the development of mining. These were primarily Saxony towns and included Freiberg, Annaberg and Marienberg.
Many of the mines that Agricola refers to had been in existence for many hundreds of years – the Freiberg silver mines, the Goslar lead mines and the Schemnitz silver mines. As we have noted elsewhere, one of the features of ancient mines can be their extraordinary long lives and that is a function of the low levels, by today’s standards, of production in the pre-industrial era. In this regard the disasters in the 14th century, particularly the Black Death, also had a major and long lasting impact on European metal production and demand. However, with the coming of the industrial revolution mine output took off almost vertically, consequently exhausting historic mines very quickly.
Twig divining and trenching for minerals in Germany in the Middle Ages
Source: De Re Metallica
Georgius Agricola (1494-1555)
Georgius Agricola is one of the most influential figures in the history of mining. His book De Re Metallica was the core textbook on mining and metallurgy for over two centuries. It remains today a remarkable body of work, both historically significant and an unrivalled description of mining in the Middle Ages and before. In 1912 it was translated into English by American mining engineer Herbert H. Hoover and his wife Lou; Hoover subsequently became President of the USA.
Born Georg Bauer in Glauchau, Saxony, in 1494, Agricola went to Leipzig University and after graduating in 1518 he taught Greek and Latin in the city of Zwickau. He went back to teach at Leipzig but intrigued by the Renaissance he travelled to Italy where he became interested in science and obtained a degree in medicine in 1526, and where he also became known by the Latin translation of his German name. In the late 1520s he returned to Germany to Joachimstal where he took up the position of town doctor. It was at this time that Agricola became interested in mining, having invested with some success in the Gotsgaab silver mine which provided him with a lifetime income. He made an extensive study of mining techniques and metallurgy in the region around Joachimstal, which was a major mining centre.
In the 1530s Agricola moved to Chemnitz to take up another medical appointment and it was around this time that his first book on mineralogy, De Natura Fossilium, was published. He continued his study of mining and metallurgical techniques in tandem with his medical practice and began work on De Re Metallica. In 1543 he married Anna, a widow, whom it is thought may have been his second wife. Agricola had at least three children by Anna and reference is made in Joachimstal records to other earlier children.
During this period he also found time to serve as burgomaster in Chemnitz, a considerable tribute to his standing as he was a staunch Roman Catholic in a Protestant country. He died in 1555 having completed Metallica a few years before and the book was posthumously published a year later. It was his last and greatest work; in total he wrote more than 20 books and pamphlets covering mining, metallurgy, medicine and religion. Anna and at least three of his children survived him and were still living in the 1580s.
De Re Metallica is comprehensive in its scope, covering hundreds of mining operations that Agricola had observed or studied. The book also includes scores of highly detailed woodcuts illustrating aspects of mining and metallurgy, and some of the first observations on geological strata and how rocks occurred in layers that could be traced for many miles. It is an historic and formidable work that stood the test of time, two centuries in fact, and it remains an invaluable work for studying the mining techniques of the Middle Ages today.
Silver
Whilst both England and Spain had historically important mining industries, central Europe was also a key mining area, encompassing the states of Germany and other countries such as Hungary and Italy. In the early 13th century near the city of Schemnitz, 60 miles northwest of Budapest, silver deposits were developed and production may have reached 5 tonnes a year. The mines continued to be substantial producers until the end of the century and other silver mines were established in the region, but Hungarian production declined as the century waned, setting off a period of silver shortages and rising prices.
The strong silver price also stimulated production in other parts of Europe – for instance silver mining near Coombe Martin in Devon in England was revived. Silver was important because of its critical role as coinage and fluctuating supplies did create considerable problems in terms of financial liquidity, which could lead to substantial fluctuations in price levels if supply expanded or contracted rapidly. It was for this reason that gold became an increasingly sought after metal, and production in the 14th and 15th centuries rose in order to fulfil this role, with mines in Transylvania and Slovakia, then known as Upper Hungary, being developed, with output totalling around 4 tonnes per year.
Perhaps the most important silver discovery in the 13th century was made near Kuttenberg, now Kutna Hora in the Czech Republic. The find generated a lot of interest and something of a rush developed with some chronicles suggesting that at least 10,000 miners had been attracted to the field; other figures were even higher. At its peak in the late 1290s Kuttenberg produced around 200,000 ozs of silver annually but production soon tailed off, although silver continued to be mined for a further 100 years. Attention then switched to a new discovery in the region at Pribram.
When output at Pribam faded too, attention turned in the first half of the 14th century to silver deposits much further south on the island of Sardinia where deliveries to the mint at Villa di Chiesa, which ran at just over 200,000 ozs, helped to make trading in the region more liquid. At the same time silver was also coming from areas to the east in Persia and Afghanistan, suggesting not only favourable regional (in the widest sense) geology but also well-trodden trading routes, and continental shortages. This latter situation (as we mentioned above) led to increasing interest in gold mining and the use of gold in coinage, as well as new sources of silver.
Another problem for European silver miners was the steady fall in silver grade mined over this period, with 100 ozs per tonne of ore common in the 12th century but 200 years later grades of 10 to 15 ozs per tonne were not untypical. Of course grade reduction is something very familiar to today’s miners, and also familiar today is the circle where falling grade leads to falling output, which in turn starts pushing the price back up, leading to a re-examination of the viability of old mining areas. This started to happen in the 14th century in the Balkans where in one case the silver mine at Srebnica in Bosnia that had produced around 50,000 ozs per year in mid-century produced a paltry 5,000 ozs in the late 14th century. As the silver price waxed and waned over the decades silver mining tended to shift away from Hungary to Balkan countries like Bosnia and Serbia.
In the second half of the 15th century Balkan silver and gold production was disrupted by the invasion and occupation of the region by Turkey. In the following century Turkey’s grip on Balkan commerce weakened, enabling silver mines to sell into buoyant markets, with Bosnian and Serbian production soaring to almost 500,000 ozs in the 1520s. Gold output from central European, Balkan and African mines exporting to Europe was also on the rise and by the mid-15th century had reached 200,000 ozs. However, there was a price