Well, I don't think TIME IS MONEY is an ontological metaphor. Coins or cash money can be said "objects", but in the conceptual metaphor,MONEY doesn't necessarily mean coins or cash (if so, how about digital money?). The confusion in demarcating structural conceptual metaphor and ontological conceptual metaphor arises from the source to be mapped. Lakoff and Johnson(1980) takes as the source domain things which are "physical objects and substance" or "entities", to which water, tub, and sun belong while money and war don't. However, the boundary between the two are not clearcut. Take a look at " ANGER IS FIRE". It seems that it may fall into both categories.