HEIRS OF THE REVOLUTION: X-RAY DIFFRACTION AND THE BIRTH OF THE MINERALOGICAL SOCIETY OF AMERICA
Although US mineralogists initially witnessed the revolution as spectators rather than as participants, there are reasons to connect the rise of a professional mineralogical society in the USA with the XRD revolution. X-ray diffraction re-defined minerals in a fashion that opened a new direction for specialized research, and it thereby differentiated modern mineralogy from traditional petrology. Somewhat paradoxically, the influence of the new technique is apparent in the discrediting of scores of minerals on the basis of X-ray diffraction data in the 1920s and 1930s. Not surprisingly, many of these minerals were poorly crystalline nanominerals common to soils and/or biomineralization processes. The continuing force of the revolution is revealed in a counter-reaction a century later, as mineralogists have renewed their focus on phases at the boundary between crystals and glasses, leading to reconsiderations of the meaning of crystallinity.