138 FIELD ‘COLUMBIAN MusEUM—GEOLOGY, VOL. I. 
“¢76. [FE 1060.] Wall rock from the Clara mine.”’ 
This is a gray, coarsely crystalline and very quartzose pyroxene 
dacite. It is unaltered, except for the feldspars, which are so muoh 
kaolinized that the varieties cannot be determined. The phenocrysts 
of quartz, pyroxene and plagioclase are very much corroded, and 
retain little of their original outlines. The ground mass consists 
of an indeterminate mixture of rather large lath-shaped crystallites. 
The quartz is very abundant. ; 
so“. Quartz, ore from the Clara mine,’ 
‘©78. [E 1061.] Quartz and arsenopyrite, ore from the Glakis 
mine.”’ 
Firm, unweathered granular quartz, with a streak of coarse 
arsenopyrite crystals along the center. 
‘¢79, Quartz and arsenopyrite, ore from the Clara mine.” 
‘¢80. Granite from the Clara mine.” 
This specimen is not in the Museum collection, and consequently 
could not be examined. The remarks under specimen No. 66 will 
apply here, and the specimen is doubtless a pyroxene dacite. 
‘*81.  Decomposed granite from the Clara mine.’”’ 
This specimen also is not in the present collection. The speci- 
men is doubtless an altered form of specimen No. 80, and is here 
considered to be an altered dacite. 
“82. Hornblendic rock, false wall in the Clara mine, 
‘Like the two preceding, this specimen is not in the Museum 
collections. From analogy with a number of rocks, given the same 
or similar names in the catalogue, there is little doubt but this is a 
specimen similar to No. 133, that 1s, a chlorite schist, resulting 
from the alteration of andesite or trachyte. 
‘¢83. Quartz, ore from the Clavellina mine.”’ 
‘84. Quartz, ore from the Clavellina mine.” 
‘¢85. Quartz and arsenopyrite, ore from the Clavellina mine.”’ 
‘¢86. Quartz, ore from the Chuchero mine.” 
bine Ore from the Santa Catalina mine.” 
GOLD MINING DISTRICT OF ANORI. 
Anori, at an elevation of over 4,700 feet, saw the beginning 
of vein’ mining im Colombia. About 1852 the first veins were 
worked, and crushing machinery put in. The country rock is mica 
schist, according to Restrepo, and the deposits are of the class 
vetas de cajon. The ores, like those of Amalfi, are arsenopyrite 

