Botallack Tin Mines, my favorite place

My favorite place in the whole wide world - 
Botallack Tin Mines, St. Just, Cornwall.

Botallack, the most beautiful spot I know where the land meets the sea, where the salty air fills the lungs, where my grandfather once worked, digging for tin a mile under the sea.

These tin mines were opened in 1721, and closed in the 1920s, although tin mining in Cornwall had been started a thousand years BC. In fact, tin extraction of tin in South west Cornwall can be dated to the beginnings of the Bronze Age around 3000 BCE. 

The following is taken from Wikipedia. 

'Tin was much sought after as addition to copper increases its hardness, lowers the melting temperature, and improves the casting process by producing a more fluid melt that cools to a denser, less spongy metal. This was an important innovation that allowed for the much more complex shapes cast in closed molds of the Bronze Age. This created the demand for rare tin metal and formed a trade network that linked the distant sources of tin to the markets of Bronze Age cultures.

Cornwall was an  important source of tin for throughout ancient times, and may have been the earliest sources of tin in Western Europe, but within the historical period they only dominated the European market from late Roman times in the 3rd century  with the exhaustion of many Spanish tin mines. Cornwall maintained its importance as a source of tin throughout medieval times and into the modern period.

Cassiterite (SnO₂), the tin oxide form of tin, was most likely the original source of tin in ancient times.  Cassiterite often accumulates in alluvial channels as placer deposits due to the fact that it is harder, heavier, and more chemically resistant than the granite in which it typically forms. These deposits can be easily seen in river banks as cassiterite is usually black, purple or otherwise dark in color, a feature exploited by early Bronze Age prospectors. It is likely that the earliest deposits were alluvial in nature, and perhaps exploited by the same methods used for panning gold in placer deposits.

The importance of tin metal to the success of Bronze Age cultures and the scarcity of the resource offers a glimpse into that time period’s trade and cultural interactions, and has therefore been the focus of intense archaeological studies. 

Wheelpit at a medieval tin mine in Dartmoor, United Kingdom

Europe has very few sources of tin. It was therefore of extreme importance throughout ancient times to import it long distances from Cornwall. 

It has been claimed that tin was first mined in Europe around 2500 BCE in Erzgebirge, and knowledge of tin bronze and tin extraction techniques spread from there to Brittany and Cornwall around 2000 BC. However, the only Bronze Age object from Central Europe whose tin has been scientifically provenanced is the Nebra sky disk, and its tin (and gold, though not its copper), is shown by tin isotopes to have come from Cornwall.

 Available evidence thus points to Cornwall as the sole early source of tin in Central and Northern Europe.

Brittany - adjacent to Cornwall on the Celtic Sea - has significant sources of tin which show evidence of being extensively exploited after the Roman conquest of Gaul during the first century BCE and onwards . Brittany remained a significant source of tin throughout the medieval period.'