Asphalt bụ mmiri mmiri ara ehi viscous nke ukwuu nke nwere elu ojii ma na-agbaze na carbon disulfide (mmiri na-esi ísì ụtọ na-acha edo edo, na-esi ísì ụtọ). Ha na-adịkarị n'ụdị asphalt ma ọ bụ tar.
Enwere ike kewaa asphalt ụzọ atọ: coal tar pitch, petroleum asphalt na eke asphalt: n'ime ha, coal tar pitch bụ ngwaahịa sitere na coking. Mmanụ ala asphalt bụ ihe fọdụrụ mgbe a gbasasịrị mmanụ crude. A na-echekwa asphalt nke anụ ahụ n'okpuru ala, ụfọdụ na-etolitekwa ebe nchekwa mineral ma ọ bụ na-agbakọba n'elu ala nke ụwa.
A na-enweta bitumen n'ụdị asphalt site n'ịnụcha mmanụ crude site na nbibi. Ha nwere isi ihe na-esi esi na mmanụ crude ma bụrụkwa ihe dị arọ na mmanụ crude, ya mere a ga-ahụ ha n'ala ala ụlọ elu.
A na-enweta asphalt n'ụdị tar site n'ịgwọ ihe ndị dị ndụ (karịsịa coal) site na carbonization.
A na-ejikarị asphalt eme ihe n'iwu, dị ka okporo ụzọ. A na-akpọ okporo ụzọ ndị e ji asphalt na ajịrịja gwuo ụzọ asphalt.