Quartz Alpha/Beta Displacive Transformation

The movie clip to the left shows a fragment of alpha quartz displacively transforming to beta quartz as it is heated to the temperature of 573.1 deg. C. The displacive transformation is marked by a sweeping change in interference color.  In cross-polarized light, the fragment of alpha quartz appears purplish, but rapidly changes to pinkish-orange as the "front" of beta quartz sweeps from right to left.   Note the opposite occurs upon cooling through 573.1 deg.C.  The change in interference color is subtle, but notable.

Return to list of movies

Return to the Mineralogy home page

Page Created: Sept, 1998; Last modified: Aug, 2007