Soilguy, the argument goes that the half life of C14 is only a few thousand years. After a billion years, there should be no measurable amount of C14.
This is the same argument put forth by anyman. It's predicated on the assumption that C14 is ONLY created in the atmosphere. As you're aware, it's is a common technique used by creationists to look at some arcane factoid that most people are not likely to be familiar with and say how that UTTERLY refutes evolution. They like to pick something where they're not likely to be challenged. After all, they're not likely to do any homework themselves, because they're too intellectually lazy.
Find an interesting, but unexpected fact, make an assertion, and then move on to the next thing you can misrepresent. But keep throwing that first factoid out as an "unanswered question."
Here's an explanation conveyed to talk.origins by an actual scientist:
http://www.talkorigins.org/faqs/c14.html No reason to believe the carbon in diamonds would react to radiation from uranium any differently than the carbon in coal.
When you have no scruples and you just want to confuse the subject and you're too intellectually lazy to do any real research, this kind of claim is your bread and butter.
It's amazing anyone believes in evolution with all those Nobel Laureates pub-jacking, er, uh, "doing original research" at the ICR and Discovery Institute.
