Trinitite is the name given to the soil that was fused into a glass-like consistency by the heat from the Trinity Test, the world's first nuclear explosion, the Trinity nuclear bomb test on July 16, 1945, near Alamogordo, New Mexico. The glass is primarily composed of arkosic sand composed of quartz grains and feldspar (both microcline and smaller amount of plagioclase with small amount of calcite, hornblende and augite in a matrix of sandy clay that was melted by the atomic blast. It was first academically described in American Mineralogist in 1948. It is mildly radioactive but safe to handle. Two  ~25-.33" specimens in an acrylic case.