The basis for the first proposition seems to be that when granite is melted and then allowed to cool, it does not reform with the same crystal structure, but instead cools to form rhyolite. This suggests to Gentry that granite cannot form naturally, but must be the result of supernatural activity. Both propositions will be evaluated in the succeeding paragraphs of this review. Before proceeding, it should be pointed out that belief in ex nihilo creation, the fall of man, and the Noachian flood does not rest on the acceptance or rejection of the thesis presented. If Gentry is wrong in his understanding of the evidence, the validity of biblical creationism is not in jeopardy.
Biblical creationism is supported by many other kinds of evidence.
The key to understanding the technical aspects of many problems is the dividing of that problem into as many known parts as possible, thereby isolating the unknown parts for further study. Gentry's observations have suggested that these halos are independent of other radioactive elements, i.e., are not derived from the systematic radioactive decay of U-238. On the question of halo formation, Gentry and other scientists are in agreement. Pleochroic halos are the result of crystal lattice damage due to the impact of alpha particles from radioactive decay occurring at the center of the halo. Halo identification is achieved through the measurement of the halo diameter.