114 PROCEEDINGS OF THE ACADEMY OF 



Old Formula. New Formula. 



Malachite. 



2CuO.CO, Cu," = 0," = C^^+aq 



Domeykite. 



(Cuj3"As/" 



Dyscrasite. 

 Ag.Sb Sb^lAg3 



Calculated from orisfinal re- 

 cord of analysis by Rammels- 

 berg (No. 9 in Dana). 



Leucopyrite. 



FeAs^ As^ Fe" As'^ 



Fe"As/ 



Linnaeite. 



2CoS + CoSa Co"= S,"= Co^^= S,"= Co" 



C03S," 



Skutterudite. 



C0AS3 As3^=Coi^ Co^^eeAs.^ 



(Co,)^^As/ 



Sylvanite. 



(Ag,Au)Te3 Ag^Te" An'"=Te" 



(Ag^Au"OTe/i 



Jamesonite. 



2(Pb,Fe)S + Sb,S3 Pb"=S/'=Sb"' S" Pb" 



_S" Sb"^=S" 

 with Fe replacing Pb, or 



Pb,"Sb,/"S3" 



Chalcostibite. 



Cu,S + Sb,S3 (CuJ"=S3"=Sb"^ = S," 



^ (Cig"(Sb-S,")3^ 



Bournonite. 



3(CuPb)S + Sh,S, Sb"i= S3" = Pb.," S" Sb"i= 



= S,"=(Cu,)" 

 (Pb,"(Cu.,)")(Sb"^S3")/" 



