When I went to school (Quite a few moons ago) Mexico was in North America, and there were 3 Americas North, Central and South.
Then my kids were taught that Mexico was in Central America. I guess when we weren't looking, someone pushed that country a tad more south.
Then we had free trade tween Canada US and Mexico, which kinda confirmed my earlier geography classes.
Anyways, in no wat was I associating Mexico with South America. actually the gest of the story should be that "If Oil can't make it as a commodity, then .....well I guess Gold will do just fine.
Later