Exhausting The Earth, Ctd.

A reader writes:

As a chemist, I was surprised to hear that non-radioactive elements could go extinct.  Well, that's because it isn't true.  They may be more difficult to isolate and purify as we take them from the Earth's crust and store them in televisions and computers but they are still there!

The only elements that can leave the Earth on a permanent basis are non-stable isotopes (like Uranium 235) and gasses that are buoyant (they leave the atmosphere and are lost into space). The only gas I know of that we are running out of is Helium.  That is problematic but Gallium and Indium are not leaving earth any time soon.

We will find ways to recycle everything eventually.  We really have no choice in the matter.  When you throw something away you can take comfort that you are not preventing recycling you are just delaying it for a few years.

Of course one is not destroying an an element by placing it in a product. Still, recycling takes money and, at least at first blush, extracting trace amounts of gallium from TV sets doesn't seem like it would be economically viable.