Trinitite HPGe spectrum

Some months ago I’ve bought a trinitite sand from United Nuclear. They’re website description say:

Early in the morning on July 16th, 1945, the first Atomic Bomb was detonated at the Trinity test site in the New Mexico desert. The nuclear explosion produced a blast equivalent of 18,000 tons of TNT and a ½ mile diameter fireball – with a temperature over 10 million degrees Fahrenheit, far hotter than the surface of the Sun. The intense heat melted the New Mexico desert sand into a light green, glass-like substance which was later named “Trinitite”. The resulting crater lined with Trinitite was buried for security reasons not long after the explosion.

In a couple of weeks I’ve received this vial full of Trinitite grains.

I’ve tested it under UV light but this material not present any fluorescence. The second test is obtain a gamma-ray spectrum from it in order to see if it’s a fake or not. I’ve used my 30×40 NaI(Tl).

The scintillation crytal have a center well made for vials. In this way low energy gamma rays are collected by the crystal at the highest efficency. After several hours of analysis the result spectrum shows clarely Americium and Cesium isotopes made by neutron activation during the bomb explosion. This sand is real nuclear melted sand!!!

The first left peak is Americium and the small peak at 609keV are Bismuth and Cesium isotopes. My crystal have good sensibility but an FWHM of 11% is not enought to extract any fine detail.

UPDATE 10 October 2019

I’ve made this test again with a 63x63mm NaI(Tl) scintillation probe enclosed into a 50kg componible lead shield. The result is amazing!!!

Americium, Europium, Cesium and Potassium isotopes from the neutron activation are quiet recognizable.

My friend Stanislav Prytuliak had made a test of a trinitite sample bought on eBay using the HPGe spectrometer at Karlsrhue university.

The following picture is Copyright by Stanislav Prytuliak (C) 2019 and couldn’t be reproduced. The following picture is published by his permission.

Final conclusion? The trinitite sample is not fake!