Articles | Volume 32, issue 1
Eur. J. Mineral., 32, 167–170, 2020
Eur. J. Mineral., 32, 167–170, 2020

Letter 30 Jan 2020

Letter | 30 Jan 2020

Comment on “Water decreases displacive phase transition temperature in alkali feldspar” by Liu et al. (2018)

Herbert Kroll and Peter Schmid-Beurmann

Related authors

Na-feldspar: temperature, pressure and the state of order
Herbert Kroll, Hans Ulrich Bambauer, and Horst Pentinghaus
Eur. J. Mineral., 32, 427–441,,, 2020
Short summary

Cited articles

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Harris, M. J., Salje, E. K. H., Grittier, B. K., and Carpenter, M. A.: Structural states of natural potassium feldspar: An infrared spectroscopic study. Phys. Chem. Miner., 16, 649–658, 1989. 
Hovis, G. L.: Angular relations of alkali feldspar series and the triclinic-monoclinic transformation, Am. Mineral., 65, 770–778, 1980. 
Hovis, G. L.: Behavior of alkali feldspars: Crystallographic properties and characterization of composition and Al-Si distribution, Am. Mineral., 71, 869–890, 1986. 
Hovis, G. L., Brennan, S., Keohane, M., and Crelling, J.: High-temperature X-ray investigation of sanidine-Analbite solid solutions: thermal Expansion, phase transitions, and volumes of mixing, Can. Mineral., 37, 701–709, 1999. 
Short summary
Feldspars are the most abundant minerals in the Earth's crust. Their structural behaviour is complicated because order/disorder reactions, phase transitions, and unmixing processes interact. Liu et al. (2018) claim that the water content in the nominally dry feldspars has a profound influence on the transformation behaviour. Their arguments, however, are not sound. We point to a number of errors and omissions.