Where does epsom salt come from?
Grampa wanted to know so I (you know, the one who's always bragging up how cool "that computer thing" really is) did a search and came up kinda dry.
I know it's magnesium sulfate, so I figured it would come from magnesium mines...of which there mostly aren't any as they usually pull magnesium from seawater. I also know there was an Epsom salt mine (run by the American Magnesium Co.) near China Lake which apparently had a nifty monorail system at one time. I know it was discovered near Epsom, England. I even know there's an entire organization devoted to the promotion and use of Epsom salt.
To which grampa said, "Yeah, but where's it come from?"