There are many types of insulation that you can use for your home, but one type might be considered more interesting merely by the fashion in which it was discovered. The material that inspired rockwool was found in Hawaii. It was hanging in trees as a byproduct of volcanic activity there.
Rockwool has some properties that makes it ideal to use as insulation. Rockwool insulation is very dense, and the way the fibers are aligned makes it very effective both at blocking moving air, as well, as sound.
Rockwool is also very good at preventing fire, since it is made from actual rock.
Unlike some insulation materials used in the past, rockwool doesn’t have any major health concerns associated with it. In fact, the only side effect that exposure to rockwool could have is not due to any chemical compound used in the insulation, but mild skin irritation from the fibers.