● Rocks with concentrated amounts of metal are called ores
● Open-cast Mining: digging a large hole in the ground to obtain metal ores
● Useless mined rock is kept in unsightly spoil tips
● Spoil: mining waste
● How concentrated the ore is
● How easy it is to get the ore out of the ground (cheaper for open-cast mining than deep underground mining)
● How easy it is to extract the metal from the ore
● What price you can get for the metal you extract
● The long-term environmental cleanup costs
Extracting the Metal from the Ore
● Four Stages:
○ The ore is mined.
i. can be open-cast digging or involve tunnelling down to underground deposits (more difficult and expensive)
○ The ore is separated from impurities.
i. spoil is left by the mine
ii. spoil tips can be toxic which contain metals (i.e. copper and lead) that dissolve in the rain and leak into soil, harming plants
○ The ore is converted to the metal.
i. usually heated in air or with carbon
ii. possibility (in both cases) of a reaction with the air to produce poisonous substances (i.e. sulfur dioxide)
○ The metal formed is then purified.
● Pure metals (i.e. copper, aluminium) can be turned into useful objects
● Recycling worn/useless products is important because metals can be hard to make or very rare
● Recycling Metals…:
○ Saves money
○ Means that reserves of metal in the ground last longer
○ Avoids waste and pollution
○ Lessens the effects of…