MKASl'KKI) CKYSTAI.S. 



67 



Crystal 36 (fig. 31) shows a cubic crystal somewhat elongated 

 in the vertical direction. The form 2(102} is invariably present on 

 tlu 'so crystals, as is also generally J{112}. Figure 32 illustrates a 



A 



FIQUEE 26. Crystal 16, a combination observed on FIGURE 27. Crystal 17, showing rare forma 

 many crystals not measured. Forms: c{001},6{010}, n, j, and o. Forms: c{001}, &{010>, a{100>, 

 a{100>, wi{110>, f{210>, /{102}, #{904}, 



b 



H 



FIGURE 28. Crystal 18, show- 

 ing striations on A, Forms: 

 c{001>, 6{010>, a{100>, 



FIGURE 29. Crystal 19, showing new forms D, B, and E. 



The zone J{112}, {5.9.14}, J5{123>, /{Oil}, and m'{HO} is well 



shown. Other forms are c{001}, 6{010}, a{100}, rn{110}, /{210}, 

 , #{904}, a^lll}, p<214}, Z>{313}. 



cubic crystal apparently slightly elongated in the direction of the 

 a axis, but in reality the original crystal was elongated parallel to 

 the & axis, as the crystal shown in the drawing is incomplete, part of 



