History – Gilsonite is the mineral that was discovered in the early 1860’s, but in the mid-1880’s Samuel H. Gilson began to promote it as a waterproof coating for wooden pilings, as an insulation for wire cable, and as a unique varnish. Gilson’s advancement of the ore was so successful that, in 1888, for the first time Samuel Gilson and a partner organized the first company to mine and market Gilsonite on a commercial scale. in the beginning, Gilsonite was sold as “Selects” and “Fines”. The “Selects” was the law softening point ore with conchoidal fracture.
Higher softening point ore with a pencillated structure was known as “Fines”. Select was more expensive than finest because of its better purity, good solubility, and usefulness in the paint, stain, and varnish industries. Over time and technology advance have changed this classification system. Processing of Gilsonite now is more pure, most of the inert pollutants and newer has been removed, so today Gilsonite is more powerful, solvents make the higher softening point grades that makes users catching more attention to this mineral. Today, Gilsonite is graded by softening point (a rough measure of solubility) and particle size. All grades carry a degree of quality far superior to those first small amounts of crude Gilsonite marketed in the 1880’s.