My understanding of precious metals is that they work as currencies first because of their scarcity and second because humans increase their value because they find new uses for their rare properties (eg:silver's conductivity, gold's extreme corrosion resistance) as technology increases. Cooking oil does not seem to have much scarcity to me, and its value might decrease with technology as innovations like air frying are cutting into the cooking oil market. Gold is also easily transportable in usable quantities (coins) but would cooking oil be as easily transportable? Would it wind up being traded in paper IOUs instead, requiring a central regulating authority, like the commodities market currently is? Although hoarding cooking oil would amusingly make me like *The Simpsons'* Groundskeeper Willie: "Ach! Muh Retirement Grease!"