66 Qualitative Tests. 
Alloys, Sulphides, Arsenides, etc.—Roast, treat 
with borax on coal in R. F., then treat borax in R. F. to 
remove reducible metals. 
IN THE WET WAY. 
FeO.—1. KsFeCsNs precipitates dark-blue Fes(Fe 
CeNs):, insoluble in acids. 
2. NH.OH precipitates white Fe(OH): 
Fe:0s—1. NH:ONS produces a blood-red solu- 
tion. | 
3. NH:OH precipitates brownish Fe(OH). 
LEAD, Pb. 
WITH THE BLOWPIPE. 
On Coal.—In either flame is reduced to malleable 
metal, and yields near the assay a dark lemon-yellow 
coat, sulphur-yellow cold, and bluish white at border. 
(The phosphate yields no coal without the aid of 
flux.) ; 
With Bismuth Flua:—On Plaster.—Chrome-yel- 
low coat, blackened by (NH:):S. 
On Coal.—Volatile yellow coat, darker hot. 
Flame.-—Azure-blue. 
With Borax or 8. PhO. F. Yellow hot, colorless 
cold. Flames opaque yellow. : 
R. F. Borax bead becomes clear, 8S. Ph. bead cloudy. 
Interfering Elements. ; 
Antimony.—Treat on coal with boracic acid, and 
treat the resulting slag on plaster with bismuth flux. 
Arsenic Sulphide.—Remove by gentle O. F. 
Cadmium.—Remove by R. F. 
Bismuth.—Usually the bismuth-flux tests on plas-_ 
ter are sufficient. In addition the lead coat should 
color the R. F. blue. 
