My friend Dave has returned to the states but his postcards are still coming in. This one shows Bolivia's Salar De Uyuni, an extensive salt and mineral deposit located at an elevation of over 11,000 feet in the Andes. Bolivia holds about half of the world's lithium reserves, the majority of which are found at the Salar de Uyuni.
Dave relates that getting to Salar De Uyuni took 'two buses, a kid puking, a flat tire and his passport being held hostage overnight' which, considering some of his exploits, went rather smoothly. He also said the area is beautiful. Apparently, the flats were covered with a few inches of water that reflected the surrounding mountains and clouds and for a while it was difficult to tell up from down.
You can find a nice account of a visit to the flats by a couple a few years ago, here.