The purpose of using Gilsonite in cementing oil wells is mainly to lighten the slurry and increase its volume. Gilsonite is a solid hydrocarbon that belongs to the category of asphalts. The type of this mineral used in cementing wells has fine and coarse black grains. The amount of water required is approximately one liter per three kilograms. This size should be such that it does not block the slurry ducts and is not so small that it cannot fill the joints and cracks of the formations.

Gilsonite grain size is in the range of 200-325Mesh. Because these grains have low shear strength, they break under high pressure.

Gilsonite in Cementing Oil Well