While the indefiniteness of his descriptions makes any attempt to repeat or reproduce his work quite futile, such data and results as he does report, nevertheless, show very clearly that he could not really have been working with true Gilsonite at all,-except,- perhaps, in admixture with dominant amounts of other substances.

There are several different types and ranks of Gilsonite. Natural asphalt is classified by degrees of hardness, moisture and softening point. 

Gilsonite is hard petroleum, almost hydrocarbon, and containing the highest fuel content. 

Bituminous rock is a type of Gilsonite , the most common type in Iran, used to mix with oil base products to modify bitumen and to make high quality bitumen for high way and Airports also special Iran Gilsonite using for fluid lose control and stabilizing hole shale.