Raw bitumen, processed from Bituminous rocks, has an extremely high viscosity.
Bitumen has an extremely high viscosity, between 8 and 10 API degrees (at ambient temperatures), rendering it unusable for use in electric power stations.
Bitumen can be modified by mixing it with fresh water and a small amount of phenol-based surfactant.
[citation needed] A newer version of bitumen-based fuel has replaced the original version with an alcohol-based surfactant, making it easier to transport the fuel and eliminating the health concerns associated with the phenol group of surfactants.
It is an emulsion of natural bitumen mined from the Orinoco Belt and fresh water.