Iron is magnetic except when heated to the Curie point. The Curie point, which is sometimes called the Curie Temperature, is the temperature at which some magnetic materials undergo a major change in their structure.
The Curie point for iron is 1,418 degrees Fahrenheit or 770 degrees Celsius. At temperatures below this point, iron atoms act as mini magnets, automatically organizing themselves in the same direction so their magnetic fields are stronger. Once heated past the Curie point, iron atoms are not able to align themselves as easily, and as a result, only a weaker type of magnetism, called paramagnetism, remains.