Now this is an idea that intrigues me.
Geology, we think of it as "static", the earth is the earth and that's it, rocks, minerals, gems, they're all there, we (almost) know everything, it's just a matter of finding it.
But, imagine, after the Anthropocene, the post-holocene, how in hundreds of millions of years the geology will changed. We've combined minerals and elements in thousands of new and unexpected ways, and as the continents subduct and boil beneath the oceans those combinations will give rise to hundreds, if not thousands of new and unimagined minerals. Skyscrapers of concrete and steel and filled with glass will form pegmatites lined with giant shards of quartz, included with golden and silver phantoms and rutile needles, percolating toxic hydrocarbons and fluids melted from landfills will fill them with new minerals and gems, to be recognized, excavated and mined by creatures as far from our thinking as ours is from the dinosaurs.
Which kind of excites me, as an exercise of the imagination, but for the moment I'll have to content myself with finding those gems already here, which is proving troublesome enough. Only 4 or 5 months until Summer...