Theory:

Magnet attract only certain materials, and some they do not. The materials are categorized into two types. They are,
Magnetic materials:
Materials attracted towards a magnet are called magnetic materials. Magnetite or Lodestone is the first known natural magnet containing iron.
Example:
Iron is used to make steel which helps in the construction of buildings and rails.
 
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Iron ore and rails made of iron
 
Nickel is a magnetic material used to make coins.
 
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Nickel ore and a coin made of nickel
 
Cobalt is used in aircraft engines and is also used to colour the ceramics blue and green.
 
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Cobalt ore and ceramic bottles coloured in blue using cobalt
Non-magnetic materials:
The materials not attracted by a magnet are called non-magnetic materials.
Example:
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From clock-wise direction: Plastics, leather, rubber, and paper.

Even metals like gold and silver are non - magnetic.
 
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Gold and silver bar
Reference:
https://live.staticflickr.com/65535/50542426886_d4e5d42765_b.jpg
https://live.staticflickr.com/5564/15024772385_5102cb2db1_b.jpg
https://upload.wikimedia.org/wikipedia/commons/6/62/Cobalt_ore_2.jpg
https://p0.pxfuel.com/preview/991/735/599/auto-tires-background-rubber-stack.jpg