SCHALT.F.R.] 
MlNERALOUIOAL NOTES. 
135 
Of the pyritohedrons i is the dominant form and is always well 
developed in large broad faces, e, d, £, y occur quite frequently as 
smaller faces, while b, f, a, a, h, are rarely present as very narrow 
faces, c is also narrow but never striated, always giving perfect 
reflections. The dodecahedron, <7, is usually somewhat uneven. The 
octahedron, 0, and </, ?/, and x occur commonly, while Z-, ///, >/\ r s > were 
observed but once each. 
18. VANADINITE. 
A specimen of vanadinite, doubtless from Yuma County, Ariz., 
shows a few crystals that possess a large number of forms. The 
crystals are 3 mm. long and 2 mm. thick, and present the usual 
appearance and habit of vanadinite. The zone c m is, however, very 
rich in forms. A number of vicinal forms were encountered that 
seem characteristic of the particular specimen. Sometimes the crys- 
tals are broken, or an apparently simple crystal may be composed of 
several ones not strictly in parallel position. In such cases, each 
zone c m was carefully adjusted by itself and the angles were measured. 
A continuous line of signals was practically never encountered, each 
face being distinct and giving a sharp signal. 
The forms observed are quoted below. 
Known forms: 
f=0001 
(f = l()T0 
/> = 1120 
/<=2130 
#=3140 
d=10l3 
r=1012 
:r = 1011 
<5=5054 
^=4043 
a =3032 
/i=5053 
?/=2021 
<y=5052 
Known forms — Continued. New forms — Continued. 
2=3031 
tt=4041 
s=1121 
r=1122 
i=2131 
£=4154 
/=3252 
New forms: 
(2=5380 
/.=3034 
o=7076 
n=7075 
.1=7074 
77=7072 
#=11.0.11.3 
x=io.o.To.i 
Vicinal forms: 
26.0.26.25 
43.0.43.40 
19.0.19.10 
15.0.T5.7 
Doubtful forms: 
71=11.0.11.10 
5=9095 
D=9094 
E=8083 
G=10.0.10.3 
F=ll. 0.11.4 
