Maybe a half a dozen times in my life I have learned something that, in a minute, totally transformed and rearranged everything I thought I knew about a subject that I thought I had previously understood. This did not quite happen at the “Bowen Series” exhibit at the Seaman Mineral Museum because my knowledge of rocks/geology has always been somewhat superficial.
While the explanation card did not so state directly, I suddenly grasped that many of the rocks I have seen and collected over the years are simply different constituents of complex mixtures of oxides of the elements that make up the earth’s crust. His method clearly (to me, the metallurgist, although the museum label did not state this) involved making phase diagrams for the common rocks as he found them to form in his “famous” magma cooling experiments (Fig. 5). Later on, as I read more about Bowen in preparing this article, I saw others talk about his phase-diagram work.
Dr. Norman Bowen was originally from Canada. His PhD is from MIT, and he spent most of his working life in the U.S. Just as a funny fact, his wife is said (http://nasonline.org/publications/biographical-memoirs/memoir-pdfs/bowen-norman-l.pdf) to have hailed from Prince Edward Island, the place of origin of my first rock collection! All of the rocks shown in Figure 5 can form from the same batch of molten “mother magma.” Bowen’s work was so revolutionary that he is credited with being the father of modern “petrology,” if not modern “geology.”