Fe3C is also known as cohenite, particularly when found mixed with nickel and cobalt carbides in meteorites. This form, a hard, shiny silver mineral, was first described by E. Weinschenk[?] in 1889.
... gamma ray intensity by 50% include 1cm (0.4 inches) of lead, 6cm (2.4 inches) of concrete or 9cm (3.6 inches) of packed dirt.
Gamma rays from nuclear fallout would ...
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