Nature and Aid, September 1, 1856 ] 
SULPHURET OP IRON. 
113 
SULPHURET OF IRON. 
The “ Mundic ” 
By W. B. Lord, 
“ A LL is not gold that glitters ; ” yet tlie bright 
1 X yellow spangles which shine so brilliantly 
amongst the black treasures deposited in our coal- 
scuttles, appear to the unpractised eye uncommonly 
like it. No golden grains are these, but a combi- 
nation of iron and sulphur, innocent enough when 
united, but, separated by the agency of heat, such 
sulphurous fumes are poured forth as to make you 
devoutly wish that no dissolution of partnership 
had ever taken place ; and the careful householder 
who, tongs in hand, and with slippered feet, yawns 
sleejhly as he rakes the last glowing embers from 
the grate before retiring for the night, feels naturally 
indignant at being taken sharply by the nose by 
Mr. Brimstone, who fiercely resents the intrusion, 
attacking our nervous friend’s air-passages in a 
manner not to be endured, and making him cough 
most heartily, and probably exclaim, “ Dear me ! 
where on earth can all the brimstone come from 1 ” 
Simply then from its former partner, iron, who 
rests quietly in the form of oxide, amongst the 
ashes. Few substances are more widely dissemi- 
nated amongst the mineral productions of the earth 
than that now under consideration, and from the 
destructive effects produced on the metal iron when 
undergoing metallurgical treatment, by the sulphur 
set free from the fuel, and the contamination pro- 
duced amongst other metals by the sulphuret (con- 
sisting of two atoms of sulphur with one of iron) 
mixed with them, that it may be almost looked on 
as one of the greatest enemies the metallurgist has 
to contend against. A. very simple experiment will 
serve to show how readily sulphur and iron unite 
when the latter is heated. Place an ordinary bar 
of iron, say the size of the middle finger, in a forge 
fire until it is at a bright red heat ; when with- 
drawn, hold it in contact with a stick of common 
sulphur. The two substances will immediately 
fuze together and drop away like sealing-wax, until 
the bar is divided and falls asunder. The drops 
which have fallen are no longer iron ; it has united 
with the sulphur and become brittle, and perfectly 
useless as a metal ; in fact, it is no longer one. 
Many of the sulphurets of iron found by the miner 
in his search for mineral ores are exceedingly 
curious and beautiful, filling at times some cleft or 
cavern amongst the rocks with crystalline forms, so 
brilliant and exquisite, that we are almost led to 
believe some royal Kobold of the mine had here 
stored up his elfin regalia, or that the lamp of 
Aladin must have been, after all, a “ Davy lamp,” 
and his cave of jewels a cavity in some deep mineral 
vein. Troublesome and unprofitable as sulphuret 
of iron sometimes is, it is at others usefully em- 
ployed for many purposes connected with arts and 
manufactures. The property which it possesses of 
IV. 
of the Miners. 
Royal Artillery. 
emitting numerous sparks on being struck sharply 
against steel, obtained for it the name of “ Pyrites,” 
which is still frequently made use of. The wheel- 
lock pieces, used after the matchlock, and before 
the introduction of the flint-and-steel gun, were so 
constructed that on pulling the trigger a small 
roughened steel wheel, which, acted on by a spiral 
spring, wound up much after the manner of a 
clock, revolved rapidly against a fixed fragment of 
sulphuret of iron, thereby producing a stream of 
sparks and igniting the gunpowder placed in the 
pan beneath them. Although never treated with a 
view to the production of iron, the sulphur, we have 
already shown it to be rich in, is taken advantage of 
in the manufacture of both alum and sulphuric acid, 
sulphuret of good average quality producing about 
seventeen per cent, of sulphur more or less asso- 
ciated with arsenic. This, when burnt, leaves a 
large residue in the chamber or retort used in its 
treatment. On being removed, it is thrown together 
in heaps and exposed to air and moisture. Oxide of 
iron and sulphuric acid are thus formed, which 
unite and produce a soluble salt, — the common 
copperas, green vitriol, or sulphate of iron of 
commerce. This, when collected in proper re- 
ceivers, is crystallized on branches of trees or strings, 
and is extensively used in dyeing, the manufacture 
of ink, &c. &c. The pigment, or colour commonly 
known as “ colcothar,” or “ purple-brown,” is ob- 
tained from the refuse matters remaining in the 
heaps after the soluble salt has drained off. We 
have at times detected small quantities of gold and 
silver amongst such refuse ; but, as a general rule, 
too minute in quantity to render its extraction a 
profitable undertaking. In Bohemia, considerable 
quantities of gold are obtained by reducing the 
sulphuret to an almost impalpable powder, mixing 
it with water, and then causing “ the slimes,” as 
the mixture is called by miners, to flow through a 
number of wooden basins, placed on the slope of a 
hill ; and here it is ground with mercury. This 
immediately seizes on every stray particle of gold 
it can catch (taking it into custody, so to speak), 
and forming what is called an “ amalgam.” After 
some time the mercury, with its prisoner, is drained 
off, placed in a leather bag, and squeezed. The 
mercury forces its way in thousands of silvery 
globules through the pores of the leather, leaving 
the gold behind, a putty-like mass in the bag. 
This is heated to drive off superfluous mercury, and 
afterwards melted and refined. 
It sometimes happens that the process of de- 
composition and conversion of the “ sulphuret ” of 
iron into the “ sulphate,” takes place deep down 
amongst the coal measures, where such intense heat 
is generated as to cause spontaneous ignition of the 
