'^Aun:&7L'''}  A7iahjsis  of  a  Silver  Ore,  349 
Ignited  the  SiOg  and  weighed. 
Si02=-2363 
I  added  the  last  NO5  solution  to  the  one  I  had  reserved,  and  pre- 
cipitated the  silver  by  HCl,  washed,  dried  and  weighed  as  AgCl. 
AgCl  =  -5604  =  -4217  Ag. 
Precipitated  the  copper  and  lead  as  sulphides  by  HS,  washed, 
dried,  oxidized  by  NO5,  and  separated  the  CuO,S03  from  the  PbO.SOs, 
by  dissolving  in  water.  Filtered  off  the  insoluble  PbO,S03,  washed, 
dried  and  weighed  as  such. 
PbO,S03  -  -1491  =  -1018  Pb. 
Precipitated  the  copper  by  HS,  filtered,  washed,  dried,  ignited, 
oxidized  by  NO5,  added  a  drop  of  SO3,  again  ignited  and  weighed  as 
CuO,SO3  =  .0240  =  -0095  Cu. 
Precipitated  the  iron  as  sulphide  by  NH^S,  filtered  and  ignited  to 
oxidize,  washed  again  to  separate  the  adhering  alkalies,  again  ignited 
and  weighed  as  FcgOg. 
FeA  =  -0216  ==-0151  Fe. 
Estimated  the  sulphur  by  treating  1  grm.  of  the  powder  with  NO5 
in  presence  of  bitartrate  of  potassa  to  keep  the  antimonic  oxide  in 
solution,  and  estimated  the  sulphur  as  BaO,S03=  -9385  =  -1289  S. 
To  find  the  amount  of  chloride  of  silver,  I  treated  1  grm.  with 
and  after  evaporating  off  the  NH^O  reduced  the  AgCl  by 
caustic  soda  and  grape  sugar,  and  estimated  the  silver  in  the  metallic 
state. 
Ag  =  -0071';  eq.  of  CI.  =  -0023,  AgCl  =  -0094. 
Summing  up  then,  1  gramme  gave — 
Elements 
Corabiaed 
Ag== 
4217 
AgCl 
=  00'94 
CI  = 
0023 
=  47-60 
Sb  = 
0809"] 
fSbS3 
=  11-31 
Pb  = 
1018 
PbS 
=  11.75 
Cu 
0095 
Cu^S 
=  1-19 
Fe  = 
0151 
FeS, 
=  3-23 
S  = 
1289^ 
23-63 
SiO,= 
2363 
Loss 
00-35 
Total 
9965 
100-00 
