GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 137-3
Presentation Time: 2:15 PM


HEANEY, Peter J., Dept. of Geosciences, Penn State University, 540 Deike Bldg, University Park, PA 16802

The arrival of the Mineralogical Society of America (MSA) in 1919 followed a century of attempts to establish an organization dedicated to the scientific pursuit of Earth materials. The formation of our Society conventionally is attributed to the desire for a professional journal and the need to emerge from the shadow of the Geological Society of America. These issues were not new in 1919. Why did MSA succeed where previous efforts failed? This presentation argues that MSA’s birth is explicitly tied to the discovery of X-ray diffraction and the revolution in crystallography that attended it. An examination of the early issues of American Mineralogist clearly reveals an awareness of the crystallographic insurgency that was taking place across the Atlantic. In particular, Edgar T. Wherry, one of the founders of both the journal and the society, actively disseminated information about the new discoveries to his colleagues in the United States.

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.