The publication in 1962–1963 of the five-volume review by Deer, Howie, and Zussman (DHZ) entitled Rock-Forming Minerals was a true milestone in mineralogy, both because it coincided with the acceleration of research in the earth sciences and because the authors considered mineralogy in the context of the larger picture of geochemistry. In these volumes, the understanding of a mineral and its structure was emphasized vs. using determinative properties for identification. Thus, a more complete picture was being presented when compared to the traditional mineralogy texts, such as Dana’s Textbook of Mineralogy or Berry and Mason’s Mineralogy . The 1962–1963 edition became a resource for workers not only in mineralogy, but also in allied fields such as petrology, materials science, ceramics, agronomy, and many others. For example, by correlating the results from many different fields, the importance of systematic studies to determine the effects of temperature, pressure, and composition on crystal structures (and physical properties!) became apparent. In addition, mineral chemists using the newly developed techniques in the 1960s and 1970s, such as electron microprobe analysis, found that reference to the compilations in DHZ of mineral compositions allowed for easy determination of a mineral’s identity. The DHZ volumes were in serious need of updating even within the first decade after they were published because of the enormous expansion of knowledge in mineralogy. The first revised …