You may remember the news from last month:
Chinese ship detained for plundering WW2 wreck
Here's the rest of the story, from Ed Conway's Material World substack, June 10:
The Eerie Story of Low Background Steel
Bandits are plundering metal from old shipwrecks, in search, it seems for the world's rarest, and strangest, metal.
The other week a Chinese vessel was detained by Malaysian authorities off the coast of Johor, under suspicion of having plundered old WWII era shipwrecks in the region.
HMS Repulse and HMS Prince of Wales, both of which sank in Malaysian waters in 1941, have had large sections of their bodies and armaments stolen in this way. The practice has been going on for years - these raiders targeting shipwrecks which are also effectively war graves - but this was one of the rare occasions when someone was seemingly caught in the act.
But why, you might be wondering, would anyone go to these lengths to obtain scrap metal. The price of steel hardly merits this kind of effort and risk. So what are these raiders really after? Gold? Silver? Stolen artworks?
The answer, it turns out, is far more interesting: a very, very rare form of metal. Something called “low background steel”.
Steel itself is one of the cheapest types of metal (an alloy technically) but the type of steel we’re talking about is one of the rarest substances in the world. For low background steel doesn’t contain radionuclides, traces of radiation such as cobalt-60. These trace amounts don’t matter for most uses but when you’re making products highly sensitive to radiation - eg special scientific equipment or Geiger counters - you need this steel.
And here’s the thing: all steel made since 1945 contains radionuclides....
....MUCH MORE
