“They should pound sand — in their own countries, where the supply is ample.”
That’s a great idea. Rammed earth construction is very practical in hot, dry places. Maybe you could get a government grant to go over to the M.E., and teach the locals how to pound sand.
Rammed Earth or Compressed Earth Blocks (CEBs) require clay as a binder, usually about 30%.
(Thus endeth my totally irrelevant but technically correct comment... Kinda reminds you of the lost Helicopter in Seattle joke...)