Gilsonite created from crude oil after milions of years in high pressure and temperature which is naturally-occurring mixture of bitumen and mineral matter formed by oil seepages in the earth’s crust. Gilsonite in rock form is available in west of Iran between Ilam and Kermanshah and Iraq border.The first utahite came from Caribbean country Trinidad and Tobago and it was contenting 55% hydrocarbon and the rest minerals. Initially this kind of Gilsonite used as additive in road construction.There is another origin of Gilsonite which is coming from other city in Kuhdasht belong to Lorestan province in Iran. The hydrocarbon content is much lower than Ilam and Kermashah and it is just using for foundry.Hydrocarbon content or bitumen content of Gilsonite from Kermanshah and Ilam is first quality of Iran Gilsonite and the purity comming up to 98%.

Generally it is mineral hydrocarbon of asphaltite class which is a black solid of fairly bright luster and melts or fuses between 130 and 210C.It is soluble in carbon disulfide, carbon tetrachloride and many other non-polar organic solvent. The principal deposit of Gilsonite is found in the Gilanegharb and Ghasreshirin, Kermanshah, Iran as filling in vertical fissures in the mountain calcareous shales, limestone and sandstones.

The PUB-LTD company has the annual production to be well over eighty thousands tons with a yearly income of nearly three million dollars for the province of Kermanshah. Considering these facts, it is easy to visualize the commercial importance of this material.Iran Gilsonite is substance composed principally of complex hydrocarbons. They contain very little mineral mater or oxygenated compounds, and are largely soluble in carbon disulphide.

These veins vary in width from several meter and to twenty meters, and vary in length from a few kilometer to as much as thirty or forty km.

Some veins are believed to be fourteen hundred meter. It has been estimated that Utah has a reserve supply of sixteen million tons of this are available for commercial development.


Natural bitumen is very fragile. It shatters easily. Rolling the Gilsonite between two drums tends to give the best particle distribution to use as raw material in carbon production.

When we process the Gilsonite from chunks to powder and then heating the asphalthum powder where we drive off the high value volatiles, we get much less material, then we are able to supply volume quantity to our customer.


Gilsonite, being a hydrocarbon, is somewhat soluble in hydrocarbon solvents. It is more soluble in kerosene and naphtha than it is in crude oil. The effect of crude oil on set cement containing gilsonite is negligible beyond the dissolution of exposed gilsonite particles. Natural asphalt has a melting point of 385°f. Some softening occurs above 24(‘f and particles may tend to fuse together. Because of the temperature reduction during circulation, it can be used in wells having a static bottom-hole temperature of 300°f and slightly higher.


Using of this mineral in heavy traffic area like junction or bus station it using as additive in paving on special location of roads like bus station or signal points and junction. Due curing of pavement because of cold or high temperature, weight of trucks and cars, sun,rain,snow road construction companies are looking for new technology and material to use to improve crack and deformation and all above problem. Atdm supplying gilsonite in the medium course and fine size and playing as resistance against fatigue and deformation. All tests showing significant improvement compared other additives. Gilsonite in permanent deformation Gilsonite is using to increase the resistance to permanent deformation and prevent shoving and rutting also cracking during cold temperature.

Gilsonite using as road pavement additives in hot mix. Natural asphalt and modified Gilsonite are adding directly at the production site of the asphalt and bitumen mixing plant. To use asphalt in road construction in cold weather just use our gilsonite and no need to use any special bitumen! Just bitumen 50-70 is more than enough! Gilsonite as bitumen binder modifer Gilsonite is used as a bitumen binder modifier with various properties of binder that is modified only by Gilsonite are common, we investigate the effect of combining bitumen and Gilsonite in the same base binder. Adding 13~14% gilsonite increase performance of asphalt. Also, the viscosity of modified binders by Gilsonite is always high. We are suggesting iran Gilsonite can be used as an alternative modifier to reduce the cost of asphalt mixture production and compaction in the field. Detail of Gilsonite mixture in asphalt It has been discovered that asphalt cement can be toughened with Gilsonite and thinned with a reactive oil. Reactive oil is an oil that contains a high content of unsaturated fatty acids. By using a reactive oil, the oil would cure or react after application of the asphalt cement to the highway, thereby allowing for a lower viscosity application by curing later to prevent rutting. Gilsonite is preferably one having a melting or softening point near about 300° F. so that it is more easily softened and blended with the petroleum asphalt at such temperatures.

It should be added slowly at the vortex. Provisions should be made to recirculate the hot bitumen through recirculation piping. The most important item is that the minimum temperature should be about 170 to 175° C. Anything significantly less than this will extend mixing time. For typical (5-10%) substitution concentrations, 2-4 hours of mixing after addition is completed should be sufficient. For master batch concentrations (over 10% mineral bitumen) recirculation overnight is preferred.

Gilsonite use as an extender

Gilsonite can be used to lighten the slurry and increase the slurry yield but will still provide a relatively high-strength set cement. Large amounts of water are not required for gilsonite. The reduction of slurry density is primarily the result of the low specific gravity of the gilsonite.

Gilsonite mix water requirements

One extra gallon of water is normally used for each 25 lb of gilsonite. Normally p-eba is required to prevent gravitational separation of a material having such a wide variance in density from the slurry. Because such a small amount of gilsonite is required, it can be blended into the slurry without the use of p-eba.

Gilsonite in lost circulation

The primary use for Gilsonite is in restoring lost circulation due to the bridging action of the angular gilsonite solids at the point of lost returns. Its effectiveness is due to the particle-size distribution. The larger and medium-size particles bridge forming a network which retains the finer particles. Thus, a dense deposit is formed which is sealed by the cement. Decreasing the slurry weight by using an extender helps in controlling lost circulation by reducing the hydrostatic pressure.

Gilsonite thickening time and compressive strength

Gilsonite is an inert solid and, owing to the small amount of additional water required, does not appreciably change the thickening time of the slurry.Higher compressive strength is generally attainable when solid particles are added to a slurry without adding excessive quantities of water. Laboratory tests indicated the cements containing either gilsonite or ground coal extender have higher strengths at all ages than most other available lightweight or lost-circulation slurries at the same slurry weight, although the strength is less than that of the same neat cement systems without the gilsonite.

powder and rock generation

bituminous coal
natural bitumen lumps

Gilsonite metamorphic products of petroleum resulting from combination of influences of time, heat and pressure. Gilsonite in general have been classified by Abraham on the based on animal,vegtebale and mineral.Gilsonite as above condition found only in Gilanegharb Kermanshah. It is solid asphalt resembling coal very much in appearance.

Natural Bitumen has two types of molecules, a straight carbon and a ringed carbon. When you heat the Gilsonite, the two components separate.  The ringed carbon vaporizes and is called a volatile.  A straight carbon remains and becomes the residue, or sometimes called carbon or carbon black.We are exporting the carbon in the residue form. The volatile after cooling done can be used as a fuel and fuel should be refined to segregate sulfur or other elements and add additives.

The liquid is as a raw material in petrochemical processing and a refinery feed stock for cracking into products like gasoline. Usually Gilsonite has over 60% volatiles and under 40% residues.  Typically the residue is in the 36 to 38% range.  The volatiles are labeled typically as the amount “lost in ignition”.