There's been a lot of controversy on this one-- both in the 'archeology biz' and on these threads. Obviously what the daters have to do is carbon date a piece of carbon that's found 'near' the stone. How near is 'near' enough? That one is simple: it has to be convincing enough to impress either the journal that publishes the findings, or to impress your next funding source.
That has given the 'scientists' a lot of leeway.
There are two aspects of this problem that I find particularly irritating. One is that the pressure is on to use all available wiggle room to chalk up records-- the 'earliest' find, the 'most advanced' site, etc. The other problem is how all this creates so much static drowning out any really solid discovery.
OTOH, it sure keeps the funding/publishing faucets turned on full.