GC: n

S: http://www.bp.com/content/dam/bp-country/en_au/products-services/bp-bitumen/all-pages/Bitumen-basics.pdf (last access: 30 July 2015); http://www.eurobitume.eu/bitumen/what-bitumen (last access: 29 March 2014).

N: 1. mid-15c., from Latin bitumen “asphalt,” probably, via Oscan or Umbrian, from Celtic *betu- “birch, birch resin” (compare Gaulish betulla “birch,” used by Pliny for the tree supposedly the source of bitumen).
2. Bitumen is an oil based substance. It is a semi-solid hydrocarbon product produced by removing the lighter fractions (such as liquid petroleum gas, petrol and diesel) from heavy crude oil during the refining process. As such, it is correctly known as refined bitumen.
3. In North America, bitumen is commonly known as “asphalt cement” or “asphalt”. While elsewhere, “asphalt” is the term used for a mixture of small stones, sand, filler and bitumen, which is used as a road paving material.
4. The asphalt mixture contains approximately 5% bitumen. At ambient temperatures bitumen is a stable, semi-solid substance.
5. bitumen, dense, highly viscous, petroleum-based hydrocarbon that is found in deposits such as oil sands and pitch lakes (natural bitumen) or is obtained as a residue of the distillation of crude oil (refined bitumen).
6. In some areas, particularly in the United States, bitumen is often called asphalt, though that name is almost universally used for the road-paving material made from a mixture of gravel, sand, and other fillers in a bituminous binder.
7. Bitumen is also frequently called tar or pitch.

S: 1. OED – http://www.etymonline.com/index.php?allowed_in_frame=0&search=bitumen&searchmode=none (last access: 3 September 2014). 2&3. http://www.eurobitume.eu/bitumen/what-bitumen (last access: 29 March 014). 4 to 7. EncBrit – http://global.britannica.com/science/bitumen (last access: 30 July 2015).

SYN:
S:

CR: artificial asphalt, asphalt, bituminous coal, coal, coke, concrete, petroleum, natural gas, pitch, tar.