I don't have reliable information about a specific work titled "Crude Oil (Vettriano)" by Banksy in my training data. While Banksy is known for satirical street art and mixed media works that often comment on politics and consumerism, I cannot verify the details of this particular piece or confirm its medium without risking inaccuracy. If you could provide additional context such as the year it was created or where it was exhibited, I would be better able to help you.