Many naturally occurring petroleum oils in Alberta are shown to produce carbon residues that exhibit a high degree of cohesiveness, a feature which should permit the production from these oils of asphalt binders exhibiting superior cohesive properties. Also shown is the presence of varying percentages of diluent-insolubles in commercial asphalts produced from several of the oils, and the formation of honeycomb-like structures (representing volume expansionsof up to 300 times) from some of these insolubles when determining the Ramsbottom carbon residue. In conjunction with the data available from the usual asphalt tests, these solubility and carbon residue tests may prove useful in permitting a better assessment of an asphalt with respect to properties and performance characteristics. Introduction A study of the fluidized coker distillate from Athabasca oil-sands oil showed that the high-boiling ends of the distillate provide Ramsbottom carbonresidues which exhibit excellent cohesiveness (1). One purpose of the present investigation was to determine to what extent the Ramsbottom carbon residues of naturally-occurring petroleum oils in Alberta exhibit this feature. Furthermore, the filtrates (2) obtained from the residues following partialthermal cracking of Athabasca oil contain varsol- and kerosene-insolubles and, in many instances, the Ramsbottom carbon residues of these insolubles are inthe form of honeycomb-like structures which represent volume expansions of upto 300 times (3). Consequently, a second purpose of the present investigationwas to determine whether commercial asphalts, on dilution with varsol orkerosene, yield insolubles similar to those obtained, as described above, fromthe Athabasca oil filtrates, and also if the Ramsbottom carbon residues ofthese insolubles show volume expansions.