Analysis of a new Variety of Ore of Antimony. 301 
mony- was subjected to several experiments with a view to deter- 
mine the proportion of arsenic, but the results were not success- 
ful. The object was obtained, however, in a satisfactory manner 
by the following process, 
a.) 200 grains of ore pulverized and mixed with 600 grains 
of nitrate of potash were gradually introduced into a red-hot 
porcelain crucible: this mixture occasioned but a slight deto- 
nation. The pasty mass of a clear brown was diluted with 
warm water, and sufficiently washed in this menstruum. We 
added to the alkaline liquor a slight excess of nitrie acid, of 
which a small quantity only was requisite fer saturation. The 
liquor was not made turbid by the addition of the acid : a proof 
that the potash had dissolved none of the antimony. I poured 
in lime water, which occasioned a voluminous precipitate. This 
precipitate when washed and dried was mixed with one-third 
its weight of charcoal, and sublimed in a small retort. The 
metallic arsenic sublimed in a shining crystalline stratum weighed 
194 grains. The residue im the retort mixed with one-half its 
weight of boracie acid, and heated again, sublimed two grains 
and a half more of metallic arsenic. 
b.) ‘The brownish substance when well washed was digested 
with a mixture of seven parts of muriatic and one of nitric acid : 
almost complete solution was the consequence. The antimony 
was precipitated from the filtered liquor by water. 
The precipitate when well dried weighed 116 grains. As in 
a comparative experiment 100 parts of metallic antimony gave 
130 of white oxide, the 116 grains represent 89 grains of metal- 
lic antimony. 
C. In order to determine with equal accuracy the quantity of 
sulphur in this ore, 100 grains were distilled with nitric acid, and 
this operation. was repeated with additional portions of acid until 
all the sulphur had disappeared from the solid residue. The 
matter remaining being well washed by water, and the liquor 
mixed with muriate of barytes, gave 102 grains of sulphate of 
barytes, in which the sulphuric acid answers to 144 grains of 
gulphur. 
The constituent parts of this ore will therefore be, saving a 
few fractions, 
Niekel-metal oi.:5) seston, AQ) ase viereapd es 28°50 
Antimony-metal ....... Bd) ........ 44°50 
Arsenic-metal ......5.. Ba). P 
REIDOU teeta vee Co) cea vena 14°20 
Onde of roms pies AC) sds sess 4°50 
