On the territory of the United Kingdom, there is a picturesque settlement called Castleton. It was built at the foot of a mountain, on top of which is a medieval castle. Tourists come here not only to admire the beauty of the local nature. They are also interested in the castle where medieval kings once lived. About 800 years ago, these territories were swamps and forests. Archaeologist, University of Nottingham Chris Lalak said that in the past this area was covered with waste lead.
Lead was mined and smelted here in large quantities. Winds blew lead dust on the glacier, which is located 1.5 thousand kilometers away in the Swiss Alps. Archaeologists believe that the glacier holds the secrets of lead mining. Modern technologies have helped scientists find out what events occurred in the past, how they were affected by the mining of lead and silver.
Often these two elements can be found in the same place. For the medieval English economy, extensive lead contamination was considered a sensitive barometer. Lead became popular when kings came to power who wanted to mint silver coins with their image. They began to use silver for making household items and decorating their castles.
But lead mining, as well as lead dust levels on the glaciers of the Alps, were affected by various events. These included economic crises, wars, epidemics, and changes in power. A special peak of lead deposits occurred during the period when lead became in demand by the industry. This is due to the active use of lead in paints, in the production of pipes and ceramic products.
In collaboration with Harvard University historians, researchers analyzed lead in an ice core drilled in 2013 on the Colle Gnifetti Glacier in the Swiss Alps. The drilling depth was 72 meters, and they captured two thousand years of life on the planet. Scientists used a laser to cut out tiny pieces of ice, thus obtaining 50,000 samples.
By subjecting them to chemical analysis, scientists learned about the intensity of lead deposits in the period from 1179 to 1219 BC. Scientists have even been able to compare the events that killed Henry II, Archbishop of Canterbury, and events that are related to the politics of Richard I (the Lion Heart). Industrial maximum lead production reached in 1970.