Radiocarbon dating sample size
Most radiocarbon AMS laboratories process samples using a variant of the method described by Vogel , with apparatus and processes typically optimized for samples containing about 1 mg of carbon.
However, the original anticipation of 100,000-year background levels has been “unrealized due to a variety of sample processing and instrument-based experimental constraints” .
The ICR (Institute for Creation Research) recently spent eight years on a project known as RATE (Radioisotopes and the Age of The Earth).
The RATE team claims the results have yielded convincing and irrefutable scientific evidence of a young earth.
Thus, even if larger samples like RATE’s “on the order of 100 mg”  are submitted to an AMS laboratory, only about 1 mg of carbon will actually undergo analysis.
Though Baumgardner calls a 1 mg sample “tiny” , it is generally considered “large” by AMS laboratories [e.g., 5, 7, 8], with enough carbon to provide ion source current for about a day.