
SULPHUR. 95 
Lustre resirous. Transparent to translucent. Buittle. H.= 
15—2°5. G.= 2.07. Burns with a blue flame and sulphurous 
odor. Ina closed tube it is wholly volatilized and redeposited 
on the wall of the tube. 
Native sulphur is either pure, or contaminated with clay or 
bitumen. It sometimes contains selenium, and has then an 
orange-yellow color. 
Diff. Tt is easily distinguished by its burning with a blue 
flame, and the sulphur odor then afforded. 
Obs. The great repositories of sulphur are either beds of 
gypsum and the associate rocks, or the regions of active or ex- 
tinct volcanoes. In the valley of Noto and Mazzaro in Sicily, 
at Conil near Cadiz in Spain, Bex in Switzerland, and Cracow 
in Poland, it occurs in the former situation. Sicily and the 
neighboring volcanic islands, Vesuvius and the Solfatara in its 
vicinity, Iceland, Teneriffe, Java, Hawaii, New Zealand, De- 
ception Island, and most active volcanic regions afford more or 
less sulphur. The native sulphur of commerce is brought 
largely from Sicily, where it occurs in beds along the central 
part of the south coast and to some distance inland. + It under- 
goes rough purification by fusion before exportation, which 
separates the earth and clay with which it occurs. 
On the Potomac, twenty-five miles above Washington, sul- 
phur has been found associated with calcite in a gray com- 
pact limestone; sparingly about springs where hydrogen sul- 
phide 1s evolved, in New York and elsewhere ; in cavities where 
iron sulphides have decomposed, and in many coal mines; near 
Borax Lake, in California; Inferno, Humboldt County, Nevada, 
abundant. : 
The sulphur of commerce is also largely obtained from copper 
and iron pyrites, it being given off during ie roasting of these 
Ores. 
Sulphur when cooled from fusion, or above 232° F., crys- 
tallizes in oblique rhombic prisms. When poured into water 
at a temperature above 300° F. it acquires the consistency of 
soft wax, and is used to take impressions of gems, medals, etc., 
which harden as the sulphur cools. ‘The uses of sulphur for 
gunpowder, bleaching, the manufacture of sulphuric acid, and 
also in medicines, are well known. Sulphur occurs in various 
ores as sulphides and sulphates. Among the sulphides are 
pyrite, an iron sulphide; pyrrhotite, another iron sulphide ; 
galena, a lead sulphide, the common ore of lead; chalcopyrite, 
or yellow copper ore, a copper and iron sulphide; cinnabar, a 
mereury sulphide ; argentite, a silver sulphide, ete. 
