<http://www.differencebetween.net/object/difference-between-steel-and-cast-iron/#webpage>
<http://schema.org/description>
"Difference Between Steel and Cast Iron Steel vs Cast Iron Iron is a hard grey metal, and heavier than any of the other elements found on Earth. During a process, impurities or slag is removed from iron, and it is turned into a steel alloy. This confirms that steel is an alloy, whereas iron is an element. Iron exists in natural"
<http://www.differencebetween.net/object/difference-between-steel-and-cast-iron/?replytocom=3262187>