a New Mineral from Peru. 197 



V o 52.61 



v;0 4 33.31 



CaO 9.89 



MgO 27 



A] o 0„Fe n 0, 1 89 



Silica . 1.66 



99.66 



The calcium was determined by fusion with sodium 

 carbonate and leaching with sodium carbonate water, leav- 

 ing CaC0 3 , MgC0 3 and Fe(OH) 3 insoluble. The residue 

 was dissolved in HC1; Fe(OH) 3 was removed with 

 ammonia, calcium precipitated as CaC 2 4 , filtered, dis- 

 solved and titrated with standard permanganate. MgO 

 was determined in filtrate by usual process. 



For total vanadium the fusion and titration method 

 outlined by A. H. Low in his ' ' Technical Methods of Ore 

 Analysis," 8th ed., 1919, p. 279, was followed. The van- 

 adyl was determined by direct . solution of mineral in 

 H 2 S0 4 and in atmosphere of C0 2 followed by titration 

 with standard permanganate. V 2 5 was obtained by 

 difference. 



The mineral had been kept for several months in a dry 

 warm atmosphere, the analysis being completed in Jan- 

 uary, 1921. All determinations were made in duplicate 

 and some repeated. The determinations gave an actual 

 figure of 0.42% for total water on a sample of about 0.12 

 gram, which is only a gain in weight of a chloride tube of 

 0.0005 grams or an allowable error in weighing a tube of 

 10 to 12 grams capacity. 



Assuming the alumina and iron oxides and magnesium 

 and silica to be impurities from the admixed shale, the 

 analysis may be recalculated to : . 



V o 54-. 90 



V 2 4 34.78 



CaO 10.32 



100.00 



From this we calculate 



™ %?=»- 



V.O. 3 ±™ =0.20!> 



2 4 



166 



CaO -°'-- =0.184 



56 



V A : Y A : CaO = 303 : 209 : 181 



