Analysis of x-ray diffraction powder data for five palygorskite samples shows that three of the samples are orthorhimbic and two are monoclinic. Retaining the same cell setting for all palygorskites, in one of the monoclinic samples the unique axis is b, and in the other, is a. Unit-cell parameters are in agreement with the values given in the literature. For both the monoclinic and the orthorhombic minerals systematic extinctions in hkl reflections lead to a primitive cell with an n-glide on (001), consistent with the projected structure of Bradley (1940).
|Number of pages||8|
|Publication status||Published - Jan 1969|