34 



University of California. 



[Vol. 3. 



0) 



Symbol. 





Letter. 



Symbol . 





Letter. 



Symbol. 



Gdt. 



Miller. 



Gdt. 



Miller. 



Gdt. 



Miller. 



c 











001 







+31 



311 





1 



3<x> 



310 







Goo 



010 





<-> 



+ 10.1 



10.1.1 



1 P 



+30 



301 





coO 



100 





6 



+ 12 



121 





(J 



-fo 



502 



^ 



2co 



210 





<T 



+ 3 



331 





f 



—80 



801 



m 



X 



110 





(1) 



+ 13 



131 







+fl 



522 



z 





1 20 





y 



— i 

 i 



1 1 1 



ill 





p 







11 



oo3 



130 





V 



\> 



221 



n 



+ 14 



141 



K 



01 



011 





q 



—3 



331 





H 



+41 



164 



a 



02 



021 





B 



—41 



411 





p. 



■Hi 



165 



X 



+ 20 



201 





© 



-31 



311 





V 



+11 



232 



V 



+ 10 



101 









-21 



211 





p 



-H 



123 



i 



-10 



101 





y 



—32 



321 





w 



—44 



182 



Ji 



-20 



201 





£ 



—23 



231 





s 



-34 



341 



W 



-30 



301 





d 



-12 



121 











*l> 



-40 



401 





Q 



-24 



241 









u 



-60 



601 





X 



-13 



131 









fi 



+ 1 



111 





)■ 



-11 



232 









The unit prism m is the predominating form, and the other 

 prismatic forms are very narrow. Usually the rear face of a is 

 much broader than the front one; h is usually present as 

 cleavage faces, and when the natural face does occur it is small. 

 When the base c and orthodome li are broad, the remainder of 

 the terminal forms are small and usually few in number; on the 

 other hand, when these two forms are absent, or very narrow, 

 the other terminal forms are well-developed. As a rule the 

 negative forms, that is. the upper rear forms, are larger and 

 better developed than the positive ones. A steep pyramid 

 occurs on a few of the crystals, but the faces gave very poor 

 reflections. The best readings indicate the symbols \ 10.1.1s for 

 the form, which are the same as determined by Jackson and 

 cited as doubtful. 



Eight forms given by Jackson were not observed by the 

 writer. These are [370 J, jl0.19.-0}, [19.19.6}, [771}, f 412}, 

 J 731 1, >721{, and [711}. According to him, the faces of all 

 these forms were extremely narrow, and gave either broad bands 

 of light or no wedge-reflections whatever. In all probability 

 [370} and [10.19.0} are [120}, and [19.19.6} is [331}. Many 

 of his original crystals were examined by the writer for these 

 forms, but they could not be identified. 



