The Widespread Distribution of a Novel Silica Polymorph in Microcrystalline Quartz Varieties

@article{Heaney1992TheWD,
  title={The Widespread Distribution of a Novel Silica Polymorph in Microcrystalline Quartz Varieties},
  author={Peter J. Heaney and Jeffrey E. Post},
  journal={Science},
  year={1992},
  volume={255},
  pages={441 - 443}
}
An x-ray examination of more than 150 specimens of fine-grained quartz varieties from around the world has revealed that more than 10% and as much as 80% of the silica in many samples is actually moganite, a little-known silica polymorph. Rietveld refinements of 50 powder x-ray diffraction patterns produced by fibrous quartz (agate, chalcedony) and nonfibrous quartz (chert, flint) indicate that the concentrations of moganite within each subgroup are widely distributed. The large amount of… 
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