Nickel and vanadium are found at Asphalt may be confused with coal tar, which is a visually similar black, thermoplastic material produced by the destructive distillation of coal.During the early and mid-20th century, when town gas was produced, coal tar was a readily available byproduct and extensively used as the binder for road aggregates.Common colloquial usage often refers to various forms of asphalt as "tar", as in the name of the La Brea Tar Pits.
Neither of the terms "asphalt" or "bitumen" should be confused with tar or coal tars.
Its viscosity is similar to that of cold molasses while the material obtained from the fractional distillation of crude oil boiling at 525 °C (977 °F) is sometimes referred to as "refined bitumen".
The Canadian province of Alberta has most of the world's reserves of natural asphalt in the Athabasca oil sands, which cover 142,000 square kilometres (55,000 sq mi), an area larger than England.
From the Greek, the word passed into late Latin, and thence into French (asphalte) and English ("asphaltum" and "asphalt").
In French, the term asphalte is used for naturally occurring asphalt-soaked limestone deposits, and for specialised manufactured products with fewer voids or greater bitumen content than the "asphaltic concrete" used to pave roads.