Asphaltum is natural asphalts. Asphaltum is dark-colored binder materials made up of complex, non-volatile, high molecular weight hydrocarbon chains. These can have two origins; the petroleum derivatives and the natural ones. Asphaltum have been produced from petroleum, but by a natural process of evaporation of volatile fractions, leaving the asphaltic only.
These can be found as surface runoff in terrestrial depressions, giving rise to asphalt lakes, such as those of the Kermanshah and Ilam city. Also they appear impregnating the pores of some rocks, denominating rock asphalt which called asphaltum. Thus they are also mixed with mineral elements, such as sands and clays in varying quantities, and must be subjected to further purification processes, and then be used in paving. At present, this type of asphaltum is using widely in China and India.