Trinitite
The heat of the blast vaporized the steel tower and melted the desert sand and turned it into a green glassy substance. It was called Trinitite and small pieces can still be seen in the area. At one time Trinitite covered much of the depression made by the explosion. Afterward the depression was filled and much of the Trinitite was taken away by the Atomic Energy Commission. To the west of the monument is a low structure which is protecting an original portion of the crater area. In 2004, members of the White Sands Missile Range Public Affairs Office began assisting Los Alamos National Laboratory scientists Robert Hermes and William Strickfaden in a fresh look at Trinitite and how it was formed. The two published the results of their investigation in the Fall 2005 issue of “Nuclear Weapons Journal.”
The two scientists were puzzled by spheroids within pieces of Trinitite. The spheroids looked like little droplets and suggested that instead of being baked below the explosion like a giant Trinitite brulée, the desert sand was first scooped up into the fireball. Inside the fireball, the melted sand behaved just as water does in a regular cloud: tiny droplets aggregated into bigger droplets that became too heavy to remain suspended and fell as a rain of molten glass.
These photos show Trinity Site Ground Zero still covered in Trinitite. The Trinitite was removed in 1952, but visitors to the site can still find small pieces on the ground today. Trinitite still underground can be brought to the surface by insects as well as the erosion of surface soil by rainwater and wind. 
These photos show Trinity Site Ground Zero still covered in Trinitite. The Trinitite was removed in 1952, but visitors to the site can still find small pieces on the ground today. Trinitite still underground can be brought to the surface by insects as well as the erosion of surface soil by rainwater and wind.
“Much of the layer was formed not on the ground but by a rain of material injected into the
fireball that melted, fell back, and collected on the hot sand to form the observed puddles of Trinitite, especially within the radius of the hottest part of the event,” the study concluded. “After falling to the ground, the top surface of the Trinitite layer was still heated somewhat by the fireball and thus developed a smooth surface.”
“We calculated an average fireball temperature of 8,430 Kelvin,” they reported. That’s 14,710 degrees Fahrenheit. The new theory explains the tiny spheres of glass found onsite as drops that cooled and hardened enough to keep their shape when they hit the ground. It also explains why there was Trinitite found on top of the outer edges of the asphalt used around the 100-foot tower and on some objects left in the Ground Zero area.
These three black and white photos show a closer look at the Trinitite left at Ground Zero. Plants in the area were incinerated all the way down to the roots and the stems.
All visitors to Trinity Site are warned that pocketing or otherwise removing Trinitite from Ground Zero is a federal crime and may result in fines and/or jail time.