Roars. | Minerals of the Galena-Joplin District. 477 
Typ 2(Farrington). K: +R’; 6 —4R; 7. —4R; (F: + R38) ; 
(w:+2R*?); p +R; m- +4R; (¢ —2R); (# —§R); 
(t: +4R%). 
Large crystals of amber color, oftendoubly terminated. Far- 
rington mentions crystal of this type from the Crystal cave, 
Ino mine, Joplin. Crystals referred to this type have also 
been found at the Pittsburg mine, at the Crystal Palace 
mine, and at the Roach cave, on West Fourth street, Joplin. 
Doubtless they are also found at other localities. Crystals 
from the Pittsburg mine have the following forms: K:, p., 
ne, O°, t:, we, andg-. Prof. W.O. Crosby, who has made a thor- 
ough study of the Roach cave, describes the crystals there as 
having the two ends different. One end is amber color, with 
several terminations in parallel positions. These ends have 
the following forms: K:, ¢-,t:,o-,andm-. The other end has 
but a single sharp, unmodified termination of the form K:, 
- and is dark from inclusions ef small, elongated crystals 
which bound phantom crystals. Crystals from this cave are 
often very large, measuring three or four feet in the direction 
of the vertical axis. They are represented in figure 35. The 
crystals described as type 22 might possibly be included here, 
but as they differ in some of the forms, and as the localities 
are widely separated, it is thought best to designate them as 
a separate type. Measurements on crystals of this form are 
as follows: 
CRYSTAL. Angle. measure Average. | Calculated. 
No. 1 > AN 0221,0445| 1 ME ROY || CeO OY 
No. 1 e-am- |1011,4041| 1 31 0 31 104 
No. 2 SuAg (O12 A022) 1 87 45 86 52 
No. 2. wag |0665,0221| 38 13 45 13 184 
No. 2. [ls Se 0665,0112| 4 93 59 23) 33% 
No. 3 ag. |0665r0221] 3 18 0 13 18% 
No. 4 kay |2131,0445| 1 23 40 24 50 
5 3 
ZO) 22 4 
