168 Copper Mines of Chili. (April, 
A branch of the Coquimbo and Ovalle Railroad terminates 
near the smelting works. This railroad, in addition to the 
large yield from Panulcillo, used to carry considerable 
quantities of ore from Las Cardas, Cerillos, Tambillos, An- 
dacolla, and other stations, all of which are now producing 
so little that the profits of the road have dwindled to nothing. 
Mineralogically one of the most curious copper deposits 
in Chili is at Andacolla. A large bed of indurated magnesian 
clay is more or less permeated with a black sulphuret of 
copper. In drying the clay evidently cracked, and gave rise 
to innumerable narrow fissures, which became filled with 
the copper constituents of the bed. This has since under- 
gone a very beautiful transformation in these veinlets near 
surface into silicates and carbonates; at greater depths 
into black oxide, red oxide, and metallic copper. In one of 
these miniature lodes one sees sometimes a central thread 
of undecomposed sulphuret, bordered by successive bands 
of black and red oxides and metal. 
So soft is the ground that powder is rarely used in mining 
it. But the saving in this item is almost compensated for 
by the cost of timber. Stoping is out of the question. All 
the ore is extracted from galleries, which are timbered as 
fast as they are driven, and remain open for a fortnight or 
so, when the ground crushes in the timber tunnel, and the 
miner may commence driving again in the same spot. 
The mines are situated in an arid plateau, famous from of 
old for its gold mines. The people, therefore, are accus- 
tomed to the use of the dbatea, or conical wooden dish of the 
gold washer, and therefore adopted it for the concentration 
of these ores. 
The ore as it comes from the mine is sorted, the rich vein 
stuff separated from the bed stuff and the latter crushed to 
one-fourth of an inch. Women squatted round long tanks, 
wash the crushed ore in the batea, extracting less than one- 
half of its total contents, which, however, they raise to 
25 percent. A woman will wash 2 tons in twelve hours, 
extracting about 2 cwts. of concentrated stuff. When copper 
commanded a good price, even this wasteful method of 
washing (the only one practicable from water) gave most 
profitable returns; latterly, however, the pecuniary results 
have been less favourable, and the yield of the muinerale 
has become insignificant. 
The next mine worthy of notice is the Brillador, belonging 
to Charles Lambert. It is the nearest to the sea of all the 
Chili copper mines, being not over three miles in a straight 
line from the northern sweep of the Bay of Coquimbo. 
