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A study was conducted on the microdistribution of aluminum, lithium and sodium in alpha quartz. Variations in trace element concentrations surpassing three orders of magnitude were observed on a microscopic scale. Zones containing intense and abrupt blue luminiscence were found to have the highest concentrations of aluminum and lithium. The variability of trace element concentrations was found to be growth related and was also suggested to be caused by changes in hydrogen-ion concentration.

Static and [sup.23]Na MAS and [sup.1]H MAS NMR experiments at temperatures down to 100 K as well as high temperature static and [sup.23]Na MAS NMR experiments up to 873 K were carried out to study the dynamics of the sodium cation in nitrate cancrinite. In addition, X-ray powder data were recorded at 296 K and 673 K to obtain information about long-range order changes in the structure. Low temperature [sup.23]Na NMR experiments show almost no change in signal, whereas the [sup.1]H MAS NMR spectra show the freezing of cage water motion. The two different crystallographic sodium sites cannot be distinguished in the [sup.23]Na MAS NMR spectra at low and room temperature. In contrast, two [sup.23]Na NMR signals exist at high temperatures above 673 K, a quadrupolar pattern and a Lorentzian signal. Rietveld structure refinements of powders show no change in the local environment of sodium. The strong quadrupolar coupling results from the loss of cage water and the near planar O atom coordination of Na in the [Epsilon]-cage, while the interaction of [Na.sup.+] in the channel remains similar. Thus the change in quadrupolar interaction is mainly caused by the absence of electrostatic shielding of cage water after dehydration.