CompuServe Messages

Excuse me for being a little abrupt here, but if you are asking this type of basic question, just where is the rest of your data/information coming from? I can't help but wonder if you really have the knowledge to cover the subject. But your, premise is correct. None (or at least not many) of the basic elements we really need/use are in short supply in the earth's crust (or atmosphere). They are just tied up so as to be difficult to gather economically and ecologically safely. Continual growth in our knowledge does change this, i.e. up until about the 1950s gold could only be mined if there was greater than around a half ounce per ton of rock (+ or – depending on the deposit), but now deposits are being mined that have less than 0.3 ounces per ton. Lanny