It could be either.
As I pointed out in other comments, that's how radioactivity was discovered and it is very well possible that they blundered into something exceptional by accident, it is also possible that both parties got it wrong and there are yet other effects at play (see the big gap in the t/R curve, that really needs explaining).
When Hildebrand ran the baths the silver came out bright, and stuck to the objects; the minute he left troubles started. No one knew why. Shortly before he left to go into the antique business in Charleston he showed me the secret. It was his chewing tobacco, spat into the bath from time to time. From then on, one man in each shift chewed, and the problem was solved
Any other recommendations on books about the history of MatSE/Chemistry?
Oops... I can see where that is headed.
Ignition! By John D. Clark
https://www.amazon.com/Ignition-audiobook/dp/B07CTW1M9D/ref=...
Or, maybe you’ve already read it, in which case: great job. Maybe someone else will see this comment and enjoy it.
I don’t want to spoil if for you, but I loved the last paragraph. I believe a new heroic age for the field is dawning.
This book is probably helping me cope with the extreme confusion of all the various LK-99 attempts. Like, it's going to be a hugely messy confusion and slog with lots of results that are "blend-A can meet 5 of the 7 requirements, but not the important ones. blend-B can meet 3 of the 7, but one of the important ones. blend-C looks very promising but doesn't quite meet any of the requirements." for... years.
Do you think it will be "purity" or understanding material variance/specific impurity?
It reminds me of Fogbank, the nuke material claimed to be "so secret they forgot how to make it." Part of the story of manufacturing difficulty was due to increased purity of modern materials/processes.
In a bizarre twist, the new production facility and reverse-engineered production process yielded a version of Fogbank that was of a higher purity than it had been in the past, according to the article. The problem, however, was that for Fogbank to work as intended in existing warhead designs, that previous level of impurity was actually essential. NNSA had to revise the process to ensure the final product was just as impure.
https://www.thedrive.com/the-war-zone/32867/fogbank-is-myste...