Ores

Some metals are found naturally in the Earth's crust. These are nonreactive metals such as Gold and Platinum.

Ores are rocks that contain enough of a compound to extract a metal for profit.

Extracting metals from their ores: (Extraction)

• Heating their compounds with carbon (Iron is extracted by heating Iron Oxide from Iron ore using carbon)
• Electrolysis of a molten compound (more expensive than heating with carbon due to cost of electricity - Aluminum)

The more reactive a metal is, the harder it is to extract. 

The more reactive metal is harder and more expensive to extract.