It will explode if lit or, in some cases, touched. It is powerful and can be pasted to objects to get an easy way to destroy them. Making a huge pile out of them and then setting one of them off creates a huge explosion.
Elemental Acetone Peroxide
Acetone Peroxide, (abbriveated AP) is the current heaviest stable element. It's atomic weight is 121, the heaviest element, and last element. Acetone Peroxide is created by fusing Element 119 (Acetonium) and Element 120 (Peroxidium) together.
It takes five gunpowder and three sand to craft acetone peroxide, or acetone and peroxide.