Asphalt or Asphaltene
Asphalt or Asphaltene : Ring compound materials in the oil composed of carbon, hydrogen, sulfur, nickel and other trace materials. Asphaltenes are mostly very small platelets (35 A) suspended by micelles of maltenes and resins and carried through the oil. They precipitate by agglomeration as the micelles break apart on shear, mixing with acids, or other interruption of the micelle stability