Pure heroin is rarely sold on the street. The color and consistency of black tar heroin result from the crude processing methods used to illicitly manufacture heroin in Mexico. Black tar heroin may be sticky like roofing tar or hard like coal, and its color may vary from dark brown to black. Black tar heroin is often sold on the street in its tar-like state at purities ranging from 20 to 80 percent. Black tar heroin is most frequently dissolved, diluted and injected.
Injection is the most practical and efficient way to administer low-purity heroin.
The availability of higher purity heroin has meant that users now can snort or smoke the narcotic. Evidence suggests that heroin snorting is widespread or increasing in those areas of the country where high purity heroin is available, generally in the northeastern United States. It can also be injected under the skin, which is called skin-popping. Today it is popular to smoke heroin just like crack cocaine. The euphoric effects are very short in duration.