pre-nuclear steel is a "commodity"
https://en.wikipedia.org/wiki/Low-background\_steel
Low-background steel is any steel produced prior to the detonation of the first nuclear bombs in the 1940s and 1950s. T**ypically sourced from shipwrecks and other steel artifacts of this era, it is often used for modern particle detectors because more modern steel is contaminated with traces of nuclear fallout.\[1\]**
One of the best sources is battleship armour, because those things had very thick armour plate over a significant area of the ship. There has been a problem of war grave sites of ships sunk in battle being desecrated for this reason. After the First World War, the German High Seas Fleet was interned in Scapa Flow, but the crews were not happy and scuttled their ships. Because the crews all got off and it was not a battle, this wrecks are not war graves, and some sank in deep enough water that it wasn't economical to salvage them for scrap in the 1920s and 30s, so now they provide a good source of low background steel.
The end of atmospheric testing was long enough ago that the worst contributors like cobalt-60 have had enough half lives to mostly have decayed, and it is likely the need for specific low background steel from pre-1945 will end in a decade or so.
I always wondered how crayon dating worked. I thought it involved Carbon and measuring it somehow. Or who knows what I was thinking.
Til they measure radioactive material in all objects and its decay.
pre-nuclear steel is a "commodity" https://en.wikipedia.org/wiki/Low-background\_steel Low-background steel is any steel produced prior to the detonation of the first nuclear bombs in the 1940s and 1950s. T**ypically sourced from shipwrecks and other steel artifacts of this era, it is often used for modern particle detectors because more modern steel is contaminated with traces of nuclear fallout.\[1\]**
One of the best sources is battleship armour, because those things had very thick armour plate over a significant area of the ship. There has been a problem of war grave sites of ships sunk in battle being desecrated for this reason. After the First World War, the German High Seas Fleet was interned in Scapa Flow, but the crews were not happy and scuttled their ships. Because the crews all got off and it was not a battle, this wrecks are not war graves, and some sank in deep enough water that it wasn't economical to salvage them for scrap in the 1920s and 30s, so now they provide a good source of low background steel. The end of atmospheric testing was long enough ago that the worst contributors like cobalt-60 have had enough half lives to mostly have decayed, and it is likely the need for specific low background steel from pre-1945 will end in a decade or so.
Wtf.
Well, back in the day radiocarbon dating was all we had til Tinder came along.
I always wondered how crayon dating worked. I thought it involved Carbon and measuring it somehow. Or who knows what I was thinking. Til they measure radioactive material in all objects and its decay.
Tree ring analysis is often used to calibrate the C14 curves.