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BELL SYSTEM TECHNICAL JOURNAL 



The axes (and therefore the indices) given for left-handed quartz are 

 the mirror image of those for right-handed quartz so that similar faces 

 have the same indices in both and the signs of the crystallographic axes 

 are consistent with those of the electrical and physical properties in both. 

 (Crystallographers commonly use the same set of axes for both right and 

 left-handed quartz.) Table I gives the orientation and X-ray properties 



Fig. 3.7 — Stereographic projection of normals to the atomic planes in quartz 



of the atomic planes in quartz that will reflect X-rays with appreciable 

 intensity. 



The 6, 7, and e values have been calculated from the dimensions of the 

 quartz crystal lattice as determined by X-ray investigation. The intensity 

 values were determined experimentally and are only approximate. Figure 

 3.8 shows the geometrical disposition around the A' axis of those planes that 

 are parallel to the .Y axis (column 1, Table I) together with the X-ray data 

 for these planes and the disposition around the X axis of the common single- 

 rotation cuts. Figure 3.7 is a stereographic projection of the normals of 



