Gilsonite mineral is exploited in different ways from the nature. In most cases Gilsonite or any other type of natural bitumen, is a SOLID SUBSTANCE, but depending on the area of availability the softening point can change,
for example Iran Gilsonite has softening point of mostly 160-220 degrees Celsius while Trinidad natural bitumen has a softening point below 100 degrees Celsius, making it called “Trinidad Lake Asphalt” since the material is almost liquid and soft under temperature of the sun.
Trinidad & Tobacco Lake Asphalt
Iran Gilsonite Lumps
The color of Gilsonite is basically Black in shape of lumps, and upon pulverizing it can change into a dark brown color. Also Gilsonite has constant reaction with air when exploited and out of the ground; therefore an oxidation can also affect the color of the material surface while the quality of the product remains the same. Many Gilsonite suppliers and buyers have suffered this issue over changing the physical appearance in storage which makes the end-users confused. Below you can find picture of same quality Gilsonite Powder 200 Mesh from same origin, one with brown color and the other one in Black.
– Book of “Gilsonite Veins of the Uinta Basin”