Earth seems to be running out of sand, too many mortar type buildings and products. https://www.bing.com/ck/a?!&&p=b7e5...ZWFydGgtaXMtcnVubmluZy1vdXQtb2Ytc2FuZC8&ntb=1 therealdeal.com/issues_articles/sand-trap/
Saw they are also mining rare earth metals from the sea floor--lots of them. We need to strip this earth of everything.
The problem is not the running out of natural resources, it's too many darn people. In any event, a far, far greater problem is deforestation.
Gives me an idea for a sci fi story. It will be set in the future, at a time when sand is so scarce, angry people will tell each other to go pound gold.
But, but, but.... we must have sand to make cement to cover all the area where we used to have forests.
Maybe dredge the ocean floors. The Saudi's just used the ocean floor to make these islands. I would imagine it is sand they dredged.