vin, a, i Edding field: Calcite-quartz-manganese Gold 

 Table I. — Mine-water analyses." 



[Parts per million.] 



127 



Constituent. 



Chlorine (CI2) (free) 



Chlorine (CI) (combined) 



Sulphuric-acid radicle (SO4) 



Bicarbonic-acid radicle (HCO3) 



Carbonic dioxide (CO2) (combined) 



Carbonic dioxide (CO2) (free) 



Iron and aluminum oxides (Fe203, AI2O3) — 



Iron (Fe) 



Manganese (Mn) 



Calcium (Ca) 



Sodium (Na) not determined. 



Magnesium (Mg) 



Free CO2 



No. l.b 



nil 



slight trace 



255.9 



136.6 



1.2 



slight trace 

 136.5 



9.3 

 1. 6 cc. per liter 



No. 2.c 



nil 



Slight trace 



283.4 



190.9 



0.8 



nil 

 123.3 



17.5 

 5. cc. per liter 



No. 3. a 



nil 



16.8 

 trace 



13.2 

 12.0 



2.2 

 nil 

 2.8 



• All analyses by V. Q. Gana, Bureau of Science. 



6 No. 1. Headquarters mine, Baguio. Upper workings 20 meters from the surface. Solution 

 neutral to litmus. 



c No. 2. Headwaters mine, Baguio. Forty meters from the surface. Solution neutral to 

 litmus. 



d No. 3. Colorado mine, Masbate. Solution reaction alkaline. 



The ore above the point where the first two samples of water 

 were taken is calcite and quartz carrying manganese in large 

 amounts, about 1 per cent iron pyrites, and in places some galena. 



In the analyses of these samples the large amounts of calcium, 

 sulphuric-acid radicle, and bicarbonic-acid radicle, the small 

 amounts of iron and manganese, and the absence of free chlorine 

 are noteworthy features. 



The Colorado water sample was obtained where the leached 

 ore had had most of the calcite removed by surface waters and 

 the sulphides had been mostly oxidized. This analysis is char- 

 acterized by the alkaline reaction, the large amount of combined 

 chlorine, combined carbon dioxide, and relatively high iron, as 

 well as by the absence of free chlorine. In all three samples 

 there is no agent present which could dissolve gold. 



LABORATORY EXPERIMENTS 



A mixture was made of finely ground material representing as 

 nearly as possible the active constituents of the ore bodies. This 



