Mining in the United Kingdom Castle in Cheshire is evidence of bronze production during the Bronze Age. Later, lead and copper attracted the Romans to Britain. The Romans introduced iron tools and used local slaves to mine galena, an important lead ore mineral, from which they refined lead, tin and silver. These metals were used locally and also transported by ship throughout the Roman Empire. Galena was mined from deep mines located in Scotland and Wales. The widespread availability of coal and iron was a significant factor in Europe's Industrial Revolution of the late 18th and early 19th centuries. Although less coal and iron ore
Mineral processing is not completely known and further research into their mechanisms is being performed. Depressants and activators are used to selectively separate one mineral from another. Depressants inhibit the flotation of one mineral or minerals while activators enable the flotation of others. Examples of these include CN, used to depress all sulfides but galena and this depressant is believed to operate by changing the solubility of chemisorbed and physisorbed collectors on sulfides. This theory originates from Russia. An example of an activator is Cu ions, used for the flotation of sphalerite. There are a number of cells able to be used