(Cheryl of the Clue Crew uses a magnet on a beverage can and a food can.)  In separating recyclables, a magnet is used because it will not attract aluminum, but will attract this metal, the main constituent of what we call tin cans
...... scrap 
metal, which was not separated from the waste prior to being burned,... [DOC] [TLE] Full text of "ERIC ED377034: Education & Recycling: Educator's ... [PAR] DEPARTMENT OF CONSERVATION Division of Recycling vii HOW TO USE 
THIS .... MATERIALS THAT CAN BE RECYCLED  GLASS  PLASTIC  TIN  
PAPER ....