War sand is sand contaminated by remains of projectiles used in war. This kind of sand has been found in Normandy, since the invasion of Normandy, among other places. In 1988, the sand on Omaha Beach was discovered to contain man-made metal and glass particles deriving from shrapnel; 4% of the sand in the sample was composed of shrapnel particles ranging in size between  and . Researchers also discovered trace amounts of iron and glass beads in the sand, originating from the intense heat unleashed by munitions explosions in the air and sand.