Dr. Hovind (R3): The initial C-14 content cannot be known. Different parts of the same sample often yield different ratios of C-14/C-12. Various living samples give very different ratios.

R3. With one notable exception, living creatures and plants get their carbon-14 from the atmosphere. Plants take it in directly and animals eat the plants. Studies have shown that living things are in a reasonable equilibrium with atmospheric carbon-14. Some creationists have claimed that certain plants can reject carbon-14 in favor of carbon- 12, but I have yet to see any serious scientific documentation. Different isotopes of an element are chemically similar, hence the difficulty in separating them. Thus, it seems unlikely that such claims can be defended beyond minute differences or unusual cases. Neither case would pose much of a problem for radiocarbon dating. That only leaves the initial concentration of C-14 to worry about. Topic R1 shows that the level of C-14 in the atmosphere has not varied appreciably over tens of thousands of years. Therefore, the initial C-14 content is known in any reasonable sample!

The exception is some mollusks which get much of their carbon from dissolved limestone. Since limestone is very old it contains very little carbon-14. Thus, in getting some of their carbon from limestone, these mollusks "inherit" some of the limestone's old age! That is, the limestone carbon skews the normal ratio between C-12 and C-14 found in living things. No problem! If one dates such mollusks, one must be extra careful in interpreting the data. Not every mollusk shell presents such problems, and the dating of other material might yield a cross- check. Further study might even allow correction tables. The discovery has strengthened the carbon-14 method, not weakened it! By the way, shouldn't the creationist be worried over the old carbon-14 age of the limestone?

Different parts of the same sample may, indeed, yield different C- 14/C-12 ratios. Partial contamination may affect different parts of a sample to different degrees. There are laboratory techniques for recognizing and dealing with such problems. If the sample shows evidence of being hopelessly contaminated it is pitched.

Some samples, such as a section of a tree trunk, may well contain material of considerably different ages. The interior portion of a tree trunk could easily be several hundred years older than the outer portions. Once again, the C-14/C-12 ratios would reflect this difference in age.

In summing up this point, we do know within good limits what the initial C-14 was for any reasonable sample. A sample will not have different ratios of carbon unless it has been contaminated or reflects a genuine range of ages.