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 0.06 millimetres (0.0024 in) and 1 mm (0.039 in). 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.
In 2013, Dr. Earle McBride - a researcher studying sandstone diagenesis and the textual and compositional maturation of sand during transportation - mixed samples collected from Omaha Beach in 1988 with a blue epoxy, creating an "artificial sandstone", before slicing it into thin sections. Utilising an optical microscope and an external light source, shiny, opaque grains could be identified. Although wave action had elicited rounding on the edges of some coarser grains, the shard-like angularity and corrosion of both coarse and fine grains suggested these grains were man made. It is believed that the roughness of said grains was imparted by microporous surfaces produced during production and corrosion products post-explosion.
This inspection, alongside tests revealing that the grains were magnetic, lead McBride to conclude these grains were pieces of shrapnel.