To simplify the matter, a simple exercise in order to understand the percentages of the three earthly Magnesium isotopes: Magnesium 24 has a percent abundance of 78.99%, Magnesium 25 has 10%. What is the percent abundance of Magnesium 26 ? Assuming we have no other isotopes, the total must be 100%, and we have: % of Mg24 + % of Mg25 + % of Mg26 = 100. Therefore, we obtain a percent abundance of Mg 26 = 100 (78,99 +10)= 11,01% .
In the Ubatuba sample, the result obtained shows a percent abundance of Mg 26 equal to 14,3 % ( it appears that as it was not quite clear and even rather unclear in the article, the left page giving the value of 14.3- that concerning the Ubatuba sample, it turns out that the sample’s percent abundance was effectively of the exact value see right page-of (0.4085x100 / 2.842)= 14.37368 ) plus or minus 0,7%, value which is statistically significant and indicative of the existence of a sample notably different from the earthly one. Strangely enough, neither Dr Craig nor the Colorado project did take this into account, writing “it should be noted that the statistical counting error (0,7%) does not include other analytical errors such as relative counting geometry or neutron thermalization due to the relative sample sizes. It is felt therefore that the abundance of the Mg26 in sample 4527 is in reasonable agreement with the Mg26 abundances shown in the literature”.
Some biased judgment thanks to the “other analytical errors”(sic)? Why? Asking the question is giving the answer, as recognizing the true nature of Ubatuba sample would have been an implicit recognition, an implied acceptance of the strangeness of this sample, of its unearthly origin to say it bluntly. Note the fast neutron thermalization implies a slowing down of the neutrons becoming slow neutrons when the sample size is big enough, according to the fact that the neutron energy distribution is a Maxwellian distribution (Maxwell-Boltzmann molecular speed distribution ) like a thermal motion.