■m 



208 



Jackson's Analysis of Chrysocolla. 



m 



a platina crucible, and weighed, amounted to 9.25 



grains. 



The oxide of copper was re-dissolved in muriatic acid 

 diluted with water, when 0.12 grains of silica remained 

 undissolved, which is to be added to the silica obtained 

 by process B. The solution was now supersaturated 

 with pure ammonia, when oxide of iron separated, which, 

 collected, washed, dried and ignited, did not amount to 

 more than 0.05 grain per oxide of iron. 



This ore consists, then, in 100 parts, of 



33.00 containing oxygen 29.20 : 4 



A. Water 



B. Silicic Acid 



30.12 



C. Deut Ox. Copper 36.83 

 Ox. of Iron, a trace. 



a 



It 



(( 



(( 



15.05 : 2 



7.31 



1 



Loss 



00.05 



100.00 



From which it will appear that this ore is a bi-silicate 

 of the deut-oxide of copper ^hs 4 atoms of water, and 

 its chemical formula will be 



Cu 



• ♦ 



+ 



The per-oxide of iron is evidently accidental, having 

 been derived from the gangue in which the mineral 

 occurs. This ore is of great value, as its silica renders it 

 suitable to aid in the reduction of the black sulphuret of 

 copper and iron which occurs at the same place; the 

 silica combining, in the metallurgic operations of reduc- 

 tion of the copper, with the iron, which is thus separated 

 m the slag from the copper which collects at the bottom 

 of the furnace. This green ore has lately been brought 

 to Boston by the cargo, and it is also carried from Cuba 

 to bwansey, in England, where it is used with the black 

 sulphuret to aid in the nrnr.p« „f ro^.,^f; r .i,_. 



^ 



