What is this drug?

Heroin

This drug is made from morphine. When it is pure, heroin is a white crystalline powder. When it is sell on the street, it can be present in many colours because of the many substances that can be add to it. When it is transform, it can look like at a dark brown sticky gum.
Other names: diacetylmorphine, diamorphine, black tar, dope (heroin), dust, H, horse, junk, smack, scag