BCHALLER.] 
DUMORTIERITE. 
109 
The macro prism <y=too =320 is present several times. The meas- 
ured angles vary somewhat. 
Measured. 
Calculated. 
California 
o 
58 
59 
60 
59 
59 
60 
59 
60 
59 
60 
60 
55 
42 
36 
38 
23 
14 
04 
07 
25 
23 
31 
o / 
Do 
Do 
Do 
Do 
Do 
, 59 19 
Do 
Do 
Do 
Do 
, 
The macro prism n=2cc = 210 is present four times. The reflec- 
tions were fair. 
Measured. 
Calculated. 
o 
65 
65 
65 
65 
26 
35 
19 
12 
o / 
1 ), » 
Do 
> 66 01 
Do 
The macro dome o 7 =|-0 = 102 is present once on the Arizona crystal. 
The reflections were not very good. 
The dome y = f = 203 is present on one of the California crystals. 
The face is exceedingly minute and the reflection was poor. 
On crystal No. 4 (New York) were observed two very small faces, 
giving poor reflections. 
(1) 
(2) 
v . 
o 
, 
i 
83 
46 
\ 
83 
16 
1 
SO 
19 
1 
84 
17 
17 54 
17 44 
ir, 50 
17 28 
These agree approximately with the symbol {8.1.20}, or considering 
the form vicinal to a dome, to j 205 \ . 
