232 



Penfield and Ford — Calaverite. 



relied upon, the zone was carefully studied and a record kept 

 of all especially prominent reflections. The results are sum- 

 marized in the following table : 











Number of 













Measured on 





observa- 











Symbols. 



vertical circle 





tions. 



Average. 



Calculated. 



B 2 



75-0-11 



ll°35'toll° 



48' 



3 



ll c 



43' 



11° 48' 



C 



501 



15 36 





1 



15 



36 



15 53^ 



0. 



401 



19 27- 19 



40 



2 



19 



34 



19 35 



E 



11-0-4 



26 49- 27 



56 



3 



27 



16 



27 21 



D 



304 



62 8-63 



8 



9 



62 



26 



62 4 



H 



5-0-11 



71 22- 72 



18 



7 



71 



53 



71 36 



c 



001 



89 44- 90 



4 



8 



89 



55 



89 47i 



L 



104 



99 50 





1 



99 



50 



99 45 



M, 



10-0-11 



122 24-122 



49 



4 



122 



38 



122 23 



M 



101 



124 27 





1 



124 



27 



124 55 



M 2 



li-o-io 



126 49-127 



6 



3 



126 



59 



127 32 



*i 



11-0-6 



141 41-142 



40 



4 



142 



13 



142 4 



N 



201 



143 22-144 



21 



7 



143 



56 



144 28 



^ 2 



24-0-11 



146 20-147 



14 



3 



146 



42 



146 47 



P x 



25-0-4 



167 8-167 



16 



3 



167 



11 



167 9 



R 



901 



170 14-170 



44 



2 



170 



29 



171 



B, 



11-0-1 



172 31 -172 



51 



4 



172 



44 



172 37 



R 2 



15-0-1 



174 10-175 



45 



4 



174 



55 



174 35 



Among the crystals from the Monument mine there was one 

 twin which will be described later. 



Occurrence No. < 2. — Among the speci- 

 mens sent by Mr. Bixby were some detached 

 crystals somewhat resembling those just 

 described, though certainly from a dif- 

 ferent mine. The suite consisted of a num- 

 ber of fragments and one terminated crys- 

 tal, the latter measuring about 2 mm in 

 greatest diameter and 4 mm in length. The 

 crystal faces were not bright, and it was 

 believed at first that it would be useless to 

 attempt to measure the angles, but, realiz- 

 ing the importance of extending our inves- 

 tigation to material from as many sources 

 as possible, the crystal was placed in the 

 goniometer and gave far better reflections 

 The reflections though not bright were 

 The development of the forms is repre- 



than anticipated, 

 perfectly distinct. 



sented by figure 17. The terminal forms with one exception, 



