284 



C. ANDERSON. 



The polar elements for the Mineral Hill azurite were 

 calculated from the above elements, and also directly from 

 the measured angles. The results, which are in accordance, 

 are as follows, Goldschmidt's values as given in his 'Index' 

 and 'Winkeltabellen' being added for comparison. 





Po 



Qo 



e 



Anderson 



1-03337 



•88502 



•0423 



Goldscnmidt 



1-0357 



•8797 



•0419 



Forms and Angles. 

 The forms and measured and calculated co-ordinate 

 angles for the azurite of Mineral Hill are tabulated below, 

 doubtful forms and fractions of a minute being omitted; 

 the new form is indicated by an asterisk. 



Form. 



Symbol. 



Measured. 



Calculated. 



Obs. 



<£ 



P 



* 



P 



c 



001 



90 d 



o / 



2 25 



90 d 



2 25 



20 



b 



010 







90 1 







90 



3 



a 



100 



90 



90 



90 



jj 



25 



m 



110 



49 25 



j» 



49 25 



jj 



56 



w 



120 



30 18 



j> 



30 17 



jj 



16 



I 



023 



4 4 



30 38 



4 6 



30 38 



10 



f 



011 



2 44 



41 34 



2 44 



41 34 



17 



P 



021 



1 23 



60 33 



1 22 



60 34 



14 



<£ 



201 



90 



64 40 



90 



64 39 



6 



(T 



101 



)» 



47 8 



jj 



47 7 



10 







Toi 



90 



44 49 



90 



44 46 



9 



V 



302 



5 



56 28 



jj 



56 28 



11 



V 



201 



1) 



63 44 



jj 



63 44 



27 



h 



221 



50 1 



70 2 



50 



70 3 



11 



s 



111 



50 35 



54 21 



50 33 



54 21 



4 



p 



223 



51 4 



43 17 



51 6 



43 14 



5 



k 



221 



48 50 



69 37 



48 50 



69 37 



14 



7 



121 



31 14 



64 14 



31 17 



64 15 



- 6 



R 



241 



29 47 



76 14 



29 46 



76 14 



17 



X* 



481 



30 3 



82 59 



30 1 



83 2 



6 



X 



2-18-3 



6 57 



79 26 



6 57 



79 25 



9 



From the co-ordinate angles given in the above table 

 some of the principal interfacial angles were calculated, 



