Many countries have very heavy crude oil and it can only be used to refine certain products. Saudi crude cannot be used for gasoline production because of this. Mexico and Venezuela also have almost all of their oil as heavy crude. It can be used to produce heavy bunker oil used in ships and asphalt production. In Canada's Alberta oil patch, the oilsands is also very heavy crude and must be refined in an upgrader to allow it to become a very light crude then be refined into gasoline and other light oil products. It costs a great deal more time and money to refine the heavy crudes into light grade products..A certain percentage of very heavy crude is also lost in the double refining process which is one reason it brings a much lower price.
