England's vast geological natural resources include coal, petroleum, natural gas, iron ore, lead, zinc, gold, tin, limestone, salt, clay, chalk, gypsum, potash, silica sand and slate. Agricultural resources in England include sheep, wheat, barley and arable land.
Until the late 20th century, coal was England's primary natural resource used for energy. By the 1980s, discovery of petroleum and natural gas reserves in the North Sea changed energy production, providing a cheaper alternative to coal. Today, the amount of coal produced in England is only one-fifth of what it was in the mid-1900s.
England has many natural materials, including sand, gravel and crushed rock, used in the construction industry. Clay and salt are found in the northwest of England, and china clay can be found in the very south of England in Cornwall.
England's agricultural resources are vital to the country's economy. The main breed of sheep in England is called hill sheep. They are bred in the Pennines, the Lake District and the southwestern peninsula. English sheep farmers raise lambs predominately for meat and less often for wool. Grass-fed breeds are much more important than other breeds raised on arable land because they produce lean meat. Barley, the main agricultural crop, is grown mainly for livestock feed and malting.