A continuation of the study of the partial thermal cracking of Athabascaoil-sands oil shows that maximum production of Ramsbottom carbon residue fromthe virgin oil and from its fluidized coker distillate occurs when the oil ordistillate is given an initial heating at about 800 to 825°F prior to carbonization. Residues representing the high-boiling ends of the fluidizedcoker distillate provide carbon residues which show excellent cohesiveness andpermit the production of hard low-temperature coke from non-caking Drumhellercoal and of very hard pellets (briquets) from hematite and non-caking Drumheller coal. It is possible that the coke and briquets may be strong enough to be fired directly into a metallurgical furnace. Introduction: The work reported herein represents a continuation of the study of the partial thermal cracking of Athabasca oil-sands oil and of the usefulness ofthe derived products. It deals with "gum" formation during the storage ofsolutions of the Athabasca oil, the maximum production of carbon residuematerial from the oil and its fluidized coker distillate, and the usefulness of the residue from the fluidized coker distillate as a briquetting binder. Aportion of the earlier work has been reported. Results and Discussion: Gum Formation on Dilution of Toluene Extract of Virgin Athabasca Oil: Dehydrated virgin Athabasca oil was diluted with toluene and filtered toremove extraneous mineral matter. Following removal of the toluene by heating, the toluene extract was diluted with 30 parts of kerosene at 280°F, filtered through medium-porosity fritted-disk glass filters and the precipitate washed.Table I shows that room-temperature storage of the combined filtrate and washings results in substantial amounts of precipitate, which may be consideredas "gum" formation. This stability test was continued for 246 days, by which time 54 percent ofthe asphaltenes in the virgin oil had become insoluble in kerosene and hadprecipitated out. Cognizance of this feature is important in the storage of solutions of the virgin Athabasca oil.