102 THE MINERALS OF CHILE. 



Mispklcel. — Is found with copper and cobalt minerals near Coqnimlio, with copper and 

 tungsten near Illapel, and with ruby silver, antimonial silver, and native silver in the mines of 

 Chanarcillo, in the lower jiart of the veins; also near to Carriso. A specimen examined gave — 

 Arsenic - - - - - - -44.30 



Sulphur - - - - - - - 20.25 



Iron -------- 30.21 



Cobalt -------- 5.84 



100.60 



The formula of misiiickel is Fe As -f- Fe S^, with cobalt replacing the iron to a greater or 

 less extent. 



Carbonate of Iron and Manganese. — This is described as a distinct mineral by M. Domeyko; 

 but, in all likelihood, it is merely a mixture. It accompanies the sulphuret of copper and gray 

 copper, in the silver mines of San Pedro Nolasco, in a formation of secondary stratified porphyry. 

 This sijecies is of a dark blackish gray and semi-metallic lustre ; its structure is foliated in their 

 lamina3 diverging and grouped together in such a manner that the whole forms globular concre- 

 tions, covered with small crystals of pearl spar. The mineral is soft; the powder is attracted 

 by the magnet. It dissolves readily in cold acids, and, according to M. Domeyko's analysis, 

 consists of — 



Oxide of iron ------ 32.10 



Oxide of manganese ----- 30.50 



Lime ------- 2.75 



Magnesia ------- trace. 



Carbonic acid - - - - - - 32.80 



Not dissolved ------ .35 



98.50 



MANGANESE. 



Oxide of Manganese. — This is found at Arqueros, near the silver veins in secondary porphyry. 

 The varieties that appear to exist there are psilomelane and pyrolusite. 



COBALT. 



Smaltene — Arsenical Cobalt. — This mineral of cobalt is found in Atacama, in transition and 

 secondary formation, often accompanying ruby silver, native arsenic, and arsenical nickel. It 

 occurs both crystallized and massive, possessing all the properties peculiar to this mineral. The 

 composition of the specimen examined was — 



Arsenic --.-._. 70.85 

 Cobalt ------- 24.13 



Iron -------- 4.05 



Copper .--.--- .41 



Nickel ------- 1.23 



Sulphur ' .08 



100.75 



The formula of the mineral is Co As, part of the cobalt being frequently replaced by other 

 metals. 



Cobaltene — Sidplo-Arsenical Cobalt. — This is found in Coqiiimbo, in small, brilliant, octa- 

 hedral crystals, with truncated corners. It is also found granular and massive, in pieces of 



