Radioactive green glass created when the first atomic bomb melted desert sand on July 16, 1945. The fireball reached 8,400°C, hotter than the sun's surface. It fused sand into a new mineral that exists only at nuclear test sites.
H. Hiller, CC BY-SA 3.0 de
A new mineral for a new age
At 5:29 AM on July 16, 1945, the atomic age began in the Jornada del Muerto desert of New Mexico. The Trinity test, the first-ever detonation of a nuclear weapon, released energy equivalent to 21 kilotons of TNT. The explosion's fireball vaporized the 100-foot steel tower holding the device and melted the desert floor into a glassy substance named Trinitite. The intense heat fused the arkosic sand, a mix of quartz and feldspar, into a layer of glass 1 to 2 centimeters thick across a radius of about 300 meters.
Scientists theorize the glass formed when sand was sucked up into the fiery mushroom cloud, melted, and rained back down to earth as a liquid. This molten material solidified into fragments, droplets, and beads. Most trinitite is a pale bottle green, a color caused by iron from the local sand and the vaporized steel tower. Rarer varieties also exist. Red trinitite contains copper from vaporized scientific wiring, while black trinitite has a higher concentration of iron from the tower. Though still measurably radioactive, its radioactivity has decreased significantly and it is now considered safe to handle.
A scientific artifact
Trinitite provides a physical record of a nuclear detonation. The glass contains a complex mixture of fission products, activation products from the soil and bomb components, and unfissioned plutonium fuel. Scientists can study the presence of specific radionuclides like cesium-137, europium-152, and cobalt-60 to understand the nuclear processes that occurred. The material is a man-made analog to natural glasses like fulgurites, which are formed by lightning strikes, and tektites, created by meteorite impacts.
In 2021, a remarkable discovery was made within a sample of red trinitite: a previously unknown quasicrystal. Quasicrystals have an ordered atomic structure, but unlike normal crystals, their pattern never repeats. This specific quasicrystal, with a formula of Si61Cu30Ca7Fe2, was the first ever created by humans, formed under the transient extreme pressure and temperature of the blast. The discovery shows how nuclear detonations can create exotic forms of matter previously found only in meteorites or synthesized in labs. The U.S. Atomic Energy Commission bulldozed and buried most of the trinitite in 1953. While collecting new samples from the site is illegal, pieces obtained before the ban are legal to own and trade.
💡Fun Facts
The name "Trinitite" comes from "Trinity," the codename for the first nuclear test.
Some rare red trinitite contains copper from vaporized measurement wires, and under shortwave UV light, it can fluoresce with a green or bluish glow.
In 2021, scientists found a quasicrystal inside trinitite, a form of matter with a complex, non-repeating atomic structure, which is the oldest known man-made quasicrystal.
Similar glassy materials have been found at other nuclear test sites and are sometimes referred to as "atomsite," though trinitite is unique to the Trinity location.
The Trinity Site is on the White Sands Missile Range and is open to the public only twice a year. Historically, these open houses are on the first Saturday in April and the third Saturday in October. The Stallion Gate is open from 8:00 AM to 2:00 PM on those days, and the site closes at 3:30 PM.
Admission
Free. No reservations are required.
Accessibility
The site is in a desert environment with no paved roads. A quarter-mile walk is required to reach ground zero. The area is generally flat but the terrain can be uneven.
