It is necessary to know the relationship between weight and mass of the product, because it is expressed as a percentage when it comes to the amount of natural bitumen in asphalt.
In fact, the specific gravity of natural bitumen
is the ratio of the weight of a given volume of natural bitumen to the weight of water as its volume at a given temperature.
Specific gravity is a good tool for identifying the source of natural bitumens. For example, the specific gravity of the bitumen oil is 1, and the specific gravity of the pit bulls is between 1.10 and 1.25.
Specific gravity is measured by the laboratory equipment using ASTM D70-52 standard method.