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 Rock forming minerals – typically silicates or occasionally carbonates – have a specific gravity of 2.5–3.5. High specific gravity is a diagnostic property of a mineral. A variation in chemistry (and consequently, mineral class) correlates to a change in specific gravity. Among more common minerals, oxides and sulfides tend to have a higher specific gravity as they include elements with higher atomic mass. A generalization is that minerals with metallic or adamantine lustre tend to have higher specific gravities than those having a non-metallic to dull lustre. For example, hematite, FeO, has a specific gravity of 5.26 while galena, PbS,