I only wrote this in my University Paper on the topic of resource economics 6 years ago after I had been at NASA 😄.
The resources that will be most scarce relative to its demand will be nutrients vital to sustain life, as we evolved to require minerals unique to Earth. Gold and Diamonds on the other hand are plntiful even in the nearby solar system.
The water-diamond-paradox will be turned on its head sooner or later😛