ON  LAPIS  CALAMINAKIS. 
309 
No.  2,  was  a  specimen  from  the  cabinet  of  the  Philadelphia 
College  of  Pharmacy,  and  the  only  one  of  the  six  specimens 
examined  that  contained  zinc.  It  was  of  a  very  light  brown 
color,  and  before  the  blowpipe  gave  a  yellow  incrustation,  with  a 
white  edge,  indicating  the  presence  of  lead  and  zinc. 
Specific  gravity  about  3.9536. 
Loss  by  ignition,  . 
Sesquioxide  of  Iron, 
Oxide  of  Lead, 
Oxide  of  Zinc, 
Lime,  . 
Baryta,  . 
Silica,  . 
Sulphuric  Acid, 
Carbonic  Acid, 
FeaO, 
PbO 
ZnO 
CaO 
BaO 
Si03 
S03 
C02 
Pr.  ct. 
.50 
1.20 
2.21 
2.00 
2.26 
45,07 
18.00 
28.57 
a  trace 
99.81 
No.  3,  a  sample  from  a  wholesale  druggist  of  this  city,  was  of 
a  light  brown  color  with  a  pinkish  tint.  Before  the  blowpipe  it 
gave  no  incrustation,  and  the  mass  blackened  silver. 
Specific  gravity  about  3.7615. 
Loss  by  ignition, 
Sesquioxide  of  Iron, 
Oxide  of  Lead, 
Lime,  . 
Baryta,  . 
Sulphuric  Acid, 
Silica,  . 
Carbonic  Acid, 
Fe203 
PbO 
CaO 
BaO 
so3 
Si03 
co2 
Pr.  ct. 
.00 
1-50 
a  trace 
1.40 
62.05 
34.16 
1.00 
a  trace 
100.11 
No.  4,  was  obtained  from  a  wholesale  druggist  of  this  city. 
Before  the  blowpipe  it  gave  no  incrustation.  Mass  blackened 
silver. 
Analysis. — Matter  insoluble  by  long  digestion,  and  subsequent 
boiling  in  hydro-chloric  acid,  consisting  chiefly  of 
Sulphate  of  Baryta, 
Oxide  of  Lead, 
Sesquioxide  of  Iron, 
Carbonate  of  Lime, 
PbO 
Fe203 
CaO,C02 
Pr.  ct. 
95.00 
a  trace 
2.00 
2.40 
99.50 
