U (235-238)

Purified Uranium 235-238 (no Ra-226)

Natural

α, β, γ radiation

Half-life: 4,5 billion years

Main emission lines: 65keV, 95keV, 185keV, 750keV, 1001keV

Where detected

Uranium (without radium impurities) is found in any uranium glass, Red Fiesta glaze, or reagents with uranium compounds.
Over time, radium will begin to accumulate, but it would take millions of years for the spectrum to take on the appearance of natural uranium.

U (nat)

Natural Uranium with Radium-226

Natural

α, β, γ radiation

Half-life: 4,5 billion years

Main emission lines: 65keV, 95keV, 185keV, 750keV, 1001keV

Lines from Radium-226: 46keV, 78keV, 186keV, 242keV, 295keV, 351keV, 609keV, 1120keV, 1760keV, 2200keV

Where detected

In natural uranium, the decay product Radium-226 is always present.
However, it is absent in depleted uranium or purified uranium. Radium-226-free uranium was used in uranium glass and various ceramic dyes.
Natural uranium can be found in nature in the form of stones and rocks. It is also present in small amounts in the soil. In the decay chain of uranium, Radon-222 is also found.
When measuring natural background radiation, the spectral lines of these isotopes often appear.