Namibia in Infrared

This digital patchwork is from infrared Landsat satellite imagery of the Atlantic coast of the African nation of Namibia. The gold strands separating purple and black in some of the patches represent the beaches, where in Namibia and nearby parts of Mozambique, thousands upon thousands of diamonds could once be plucked from the sands. The bright gold color is not caused by diamonds or anything else precious; most likely, it is the bright infrared signal produced by salt, which encrusts the sands here where the extremely arid Namib Desert meets the sea.

The black patches or parts of patches in this quilt are water as seen by the satellite's infrared sensors; water generates no infrared signal at all. The purple patches are barren desert: dune fields, craters, and rock formations.

Much of this coastline is closed to tourists, as part of governmental and quasi-governmental efforts to limit access to nearby diamond mining operations. The mines themselves are mostly inland, in geologic formations that are two or three billion years old. But after a couple of billions of years of erosion from wind and occasional desert rainstorms, much of the matrix rock that held the diamonds has crumbled, and many thousands of loose diamonds have been washed down to the coast and out to sea. Diamonds are so heavy, however, that sea currents don't carry them far; waves tended to wash them right back up onto the beaches, where they rested in the (salty) sand awaiting human greed. In a couple of dozen years, miners plucked from the Namibian sands very nearly all the diamonds that nature needed a couple of billions of years to put there. Almost certainly, a few loose diamonds continue to surface from time to time on those beaches, but if you want to go look for them, of course, you'll need assault rifles and other mining implements.

The patchwork pattern here is an off-center version of an old flower-garden pattern that is usually worked up with floral fabric. I'm told that if plain fabric is properly sprayed and soaked, satellite imagery or any other picture can be printed on it with an ordinary inkjet printer. One of these days, I'd like to learn that technology and make this digital quilt into the kind of cover that can keep people warm.