Crude oil has a high concentration of hydrocarbons which are highly combustible. Hydrocarbons are an organic material that is made from a bond between hydrogen and carbon. The primary products produced from the refining of crude oil include diesel, gasoline, and other high octane fuels. Once fuels, motor oils, and solvents have been refined out of the crude oil a tar mixture is left.

The tar mixture left over from the distillation process consists of residual hydrocarbons and a high concentration of organic material, bitumen. The bitumen solution is refined further to make road construction bitumen, colored bitumen, and other compounds used for construction materials like roof shingles, flashing, and sealants.