The Institute for Creation Research has a project called RATE, whose intent was to overturn radiometric absolute dating methods as evidence for an old age of the earth. One of the arguments that they made was that diamonds contain significant levels of the radioactive carbon 14 (14C) isotope, indicating that they cannot be older than about 50,000 years old, and thus point to a young age of the earth. This sort of technical wrangle is something beloved of young-earth creationists (YECs), and indeed one such person going by the handle “tripa” has commented here on another thread about the RATE diamond study.
Physicist Kirk Bertsche has responded to the RATE diamond and coal studies with an essay hosted on the American Scientific Affiliation website. Dr. Bertsche notes a number of inconvenient facts that undercut the arguments made by ICR’s advocates, including standard procedures within radiocarbon AMS work that were ignored or not followed properly, and indications from the RATE measurement results themselves whose obvious interpretation points to sample contamination. It is an elegant take-down of yet another antievolution argument whose pseudo-technical gloss is intended to impress rather than to inform.