334 | Analysis of Argentine and Steatite. 
Carbonic acid - - Al. grs. 
Lime Pe ee 54. 
NER > ae ea - °3.25 
Magnesia and Oxide of Iron 0.75 ; ws 
Loss 1.00 probably carb. acid. 
.100.00 
If the the silex is to be considered an accidental ingredi- 
ent, arising from the specimen being associated with quartz, 
this argentine isa very pure carbonate of lime. 
Crystallized Steatite. 
Having ascertained that the mineral contained silex, 
magnesia, alumine, water, and oxides of iron and manga- 
nese, one hundred grains of a very large and fine crystal 
were analyzed to ascertain the proportion of the ingredi- 
ents. In the previous trials, the proportion of some of them 
had been found, but as they were not much different from. 
those obtained from this crystal, it was judged proper to 
rely on the results last obtained. In heating the mineral, 
there was sometimes more and sometimes less than fifteen 
per cent. of water liberated ; but the water is taken at fif- 
‘teen percent. In heating the mineral with sulphuric acid, 
there was no indication of fluoric acid, which is sometimes 
found in a variety ofsteatite. Indeed, the corrosion of the 
glass vessel in which the experiment is performed, is some- 
what equivocal, as sulphuric acid heated to 500° or 600° 
will act upon the potash or soda in some kinds of glass at 
least, and an actual corrosion take place. Oxalate of am- 
monia gave no indication of lime. The method of analiz- 
ing those magnesian minerals which are decomposed by 
