Sector Overview

Turning Ore Into Refined Metal

Metal extraction is the process of obtaining metals from their ores. An ore is a naturally occurring rock that contains a metal compound in a concentration high enough to be worth mining — which makes an ore an economic definition as much as a geological one.

Which route is used depends on where the metal sits in the reactivity series. Very reactive metals such as aluminium and magnesium are won by electrolysis of a molten compound. Moderately reactive metals such as iron, zinc and copper can be reduced with carbon or by roasting and smelting. Unreactive metals such as gold and platinum occur largely as the native metal and mainly need physical separation.

The general path is the same across most operations: mine the ore, crush and grind it until the valuable mineral is liberated, concentrate it, break the chemical bond holding the metal, then refine the product to specification. Secondary production — remelting scrap — follows a much shorter and far less energy-intensive path.