Physical Properties of Gilsonite You Should Know

Before using gilsonite in a formulation, it helps to know its key physical properties and how they are measured.

Appearance

Gilsonite is black and shiny with a conchoidal (glass-like) fracture. Powder is dark brown to black.

Softening point

Measured by the ring-and-ball method (ASTM D36), softening point is typically 150–220°C. It indicates the temperature at which the material becomes soft enough to flow under a standard load.

Penetration

Penetration at 25°C (ASTM D5) is below 1 dmm, confirming that gilsonite is a hard solid.

Specific gravity

About 1.04–1.10, close to water. This low density is useful in cement slurries and lightweight formulations.

Moisture

Usually below 1%. Low moisture prevents caking and ensures accurate dosing.

Ash

Typically below 5%. Lower ash means higher purity.

Solubility

At least 95–99% soluble in toluene or trichloroethylene.

Typical values

These values are confirmed for every shipment of Sun Gilsonite powder. For test methods, read gilsonite quality control tests.