r>8 ! 



Steiner recognised three habits, but his types I and II 

 seem very similar and almost identical with type I as 

 described in this paper. As regards the forms present 

 Steiner found, in addition, the faces y (121), « (121), j (045) 

 x (403), p (T5-0'8), M (13-0*6), but did not find the faces P 

 (223) and A (2-18'3) or the possible new faces (4'0-13) and 



(Toe;. 



The crystals were all measured on the two circle gonio- 

 meter and were oriented with the orthodome zone horizontal 

 and the a pinacoid vertical. The co-ordinate angles then 

 had to be calculated from the observed readings of the 

 horizontal and vertical circles. 



The elements as calculated from t 

 8 u P R I f p give the following r 





The average measured angle for ft is 87° 38'. 



Below is a table of the forms observed, the average 

 <i> and p angles and the theoretical <t> and p angles calculated 

 from the indices and elements. Figure 7 is a stereogram, 

 the projection being made on the plane of symmetry. 























1 * 1 



i- 



P 



4> 



1 P 



a 



100 



90 







90 







90 



! 90 















<t> 



301 



90 







64 



37 



90 



J 64 



40 







1 3 





101 



90 







47 



08 



90 





47 



07 







1 1 





ooi 



90 







2 



22 



90 







2 



22 









* 



106 



90 







7 



31 



90 







7 



29 







2 



D 



Am 



' 90 







11 



27 



90 







12 



16 







! 49 



* 



4".0.13 



! 90 







15 



31 



90 







15 



30 







I 



A 



103 



90 







16 



14 



90 







16 



54 







40 



e 



101 



90 



o 



44 



50 



90 







44 



50 











v 



302 



90 







56 



32 



95 







56 



32 











V 



201 



90 







63 



39 



90 



63 



47 







8 



i 



023 



3 



59 



31 







00 1 30 



38 



1 



31 



f 



Oil 



1 2 



57 



41 



16 



2 



41 



41 



34 



16 



18 



