498 Metals. MINER 
of its ultimate degree of purity, in confequence of its 
containing a greater or let's proportion of charcoal. This 
may in a great meafure be feparated by mechanical force, 
as hammering and rolling; but in being feparated it car¬ 
ries with it a portion of the iron. This compound of the 
charcoal and iron, which is analogous to the natural mi¬ 
neral called plumbago, is the fubftance which flies off in 
the form of brilliant fparks from a piece of iron, of a white 
or a high red heat, when (truck by the hammer on a com¬ 
mon anvil; or from thofe larger maffes which have lately 
undergone the procefs of reduction, when flattened by 
the more powerful engine of a foundery. 
Mr. David Mufhet, iron-matter, of Coleford in Glou- 
cefterfnire, has difcovered a new method, means, or pro¬ 
cefs, for refining pig or catt iron in a blalt-furnace, to 
which, when uted for this purpofe, he gives the name of 
the jmelting-refinery. By this invention, the whole or 
greater part of the metallic contents of the cinder, 
flag, or fcoria, produced fron the common refinery—of 
the flags, cinder, or fcoria, that fall at the puddling or 
roughing rollers—of the flag, fcoria, or cinder, commonly 
called hammer-flag—of the flag, fcoria, or cinder, that is 
produced from the mill-balling and puddling furnaces— 
of the fcale or (hale that is produced at the finifhing rol¬ 
lers—or of any other refufe containing iron formed in any 
Sage of the procefi? or precedes of making or manufaCtur- 
ing bar or malleable iron of every defcription—is recovered 
or revived, and brought direCtiy into the Hate of what is 
known in the trade by the name of fillers' iron, or metal, 
of a quality fit for the purpofes of the puddling-furnace 
or damping-fire : and, in effecting this, he makes ufe of 
the fuperfluous carbon or coaly matter of a portion of 
pig or cad iron continued in the (aid various flags, fcoria, 
cinder, fcale, or other refufe products containing iron ; 
converting at the fame time the iron contained in the pig 
or cad iron into fillers’ iron. Mr. Mudiet has taken, out 
a patent for this procefs, dated July 25, 1815; but the 
i'pecification is too long for us to tranfcribe. 
27. Ferrum ochra, red iron ochre, or crayon : not mag¬ 
netic : without ludre, opake, friable. Found in every 
country abounding in iron-ores: fometimes in folution 
in waters impregnated with iron, fometimes compaCt or 
hardifh, rarely fibrous in a deflate manner. Colour va¬ 
rious (hades of red or yellow, palling into brown by ex- 
pofure to the air: dreak red or yellow: it adheres to the 
tongue, dains drongly, and is principally employed in 
drawing and writing. 
28. Ferrum cserulea, or blue iron-ore: not magnetic; 
friable, earthy, without ludre: becoming blue by expo- 
fure to the air, and brownilh in the fire, changing its co¬ 
lours in a folution of foda. Found in many parts of Eng¬ 
land and Scotland, Siberia, Rufiia, Sweden, Norway, Po¬ 
land, Germany, &c. in marfliy grounds at various depths 5 
generally in an earthy date, and without any regular lhape, 
adhering to the (tones and pebbles which furround it: 
colour generally whitifli when fird taken from the foil, 
and becoming gradually of a fine blue by expofure to the 
air; though, accurding to Mr. Sowerby, it is fometimes 
blue when frefli gathered and fird broken. It dains 
Jtrongly, feels harlh to the touch, is moderately heavy, and 
diffolves readily in acids. When heated on red-hot coals 
it indames and leaves a red powder; before the blowpipe 
it becomes reddidi brown, and melts into a black bead, 
and tinges borax of a dark yellow : in water it preferves 
its colour, but becomes black in oils. It is by Klaproth 
conlidered as a phofphat of iron. 
29. Ferrum fmaltinum, or fading iron-ore: not mag¬ 
netic ; hardifh, earthy, opake, without ludre ; blue, not 
changing its colour in a folution of foda, becoming grey 
in the fire. Found near Vorau in Hungary; forming, to¬ 
gether with quartz and white micaceous gneifs, a vein 
from a quarter to half an inch thick. When fird dug 
from the mine it is of a fine blue colour, but lofes all its 
colour when thrown on red-hot cinders: with borax it 
mdts into a pale yellow tranfparent glafs, with pholpho- 
A L O G Y. Metals. 
ric acid a colourlefs one. It is not, like the lad, foluble 
in acids. It confids ofoxyd of iron, alumine, and (ilex. 
30. Ferrum fubaquofum, lowland or bog iron-ore s 
not magnetic ; without ludre, opake, of a dull colour, 
humid. Found in Great Britain, and various parts of 
Europe, in low iwampy fituations, dagnant lakes, or brook- 
waters ; fometimes maflive, but commonly in detached 
lumps of various fhapes, as placentiform, flat and round¬ 
ed, globular and kidney-form, when it is called eagle- 
Jlone ; granular or pifiform, generally perforated, fidular 
or fpongy. Colour brown with various (hades of red, 
green, yellow, blue, or grey; texture earthy, brittle. It -* 
confids of oxyd of iron combined with phofphoric acid 
and alumine. 
According to Werner, this fpecies of iron-ore is form¬ 
ed in the following manner: “ The water which flows 
into marfhy places is impregnated with a vegetable acid, 
formed from decaying vegetables, which enables it to dif- 
folve the iron in the rocks over which it flows, or over 
which it flands. This water having reached the lower 
points of the country, or being poured into hollows, be¬ 
comes dagnant; by degrees evaporates; and, the diffolved 
iron being accumulated in quantity by frelh additions of 
water, there follow fucceflive depofitions, which at fird 
are yellowilh, earthy, and of little confidence; and this 
is morafs-ore: but in courfe of time they become harder, 
their colour palfes to brown, and thus J'wamp-ore is form¬ 
ed. After the water has completely evaporated, and the 
fwamp is dried up, the lwamp-ore becomes much harder, 
and at length pafles into meadow lowland-ore, which is al¬ 
ready covered with foil and grafs. 
31. Ferrum viride, or green iron-ore: of a green co¬ 
lour, (hining, diffolving in acids with difficulty, friable. 
Found at Schneeburg, in a matrix of quartz and clay 5 
compafit, folid, or like a corroded done, oftener inveding 
or incumbent, and feldom indurated. Colour various 
lhades of green or yeliowidi green, with a dull ludre : it 
ltains the fingers, and blackens when drongly heated 5 
with borax it eafiiy melts into a yellowilh-brown opake 
glafs with (bme black (pots : it is fuppofed to confid of 
alumine, (ilex, manganele, and from 10 to 12 per cent, of 
iron. 
32. Ferrum arfenicale, arfeniat of iron, or mifpickel; 
grey or greenifh, not magnetic ; emitting arfenical va¬ 
pours when thrown on red-hot coals. Found in the cop¬ 
per-mines of Cornwall and in Spain, in fmall pieces, or 
generally crydaliized in cubes : its fraCture is granular, 
and it has no tranfparency. Specific gravity, from 3 to 
3'4 : it contains arfenical acid, oxydes of iron and cop¬ 
per, (ilex, and water, in various proportions. 
33. Ferrum (ulphuratum, fulphuret of iron, or iron 
pyrites : opake, emitting lulphurous flames and vapours 
when thrown on hot coals: The word pyrites is derived 
from the ufe to which it was formerly applied, of obtain¬ 
ing (parks by percuflion, as from the common flint and 
fleel. Pliny mentions this application of pyrites very 
particularly. It is called iron- pyrites to didinguilh it 
from copper pyrites, which it often clofely refembles. 
The fubltance known by the name of piedra de los Incas 
is a cubic form of iron pyrites, which from its fize, and 
the fplendour of its furface, was ufed by the monarchs of 
Peru as a mirror. The furfaces of cubic crydals of iron 
pyrites are in general driated in fuch a manner, that the 
lines of any one are at right angles to thofe of all the ad¬ 
joining. 
Beiides its diflinCtly-cryflalline forms, iron pyrites oc¬ 
curs in lerrated plates refembling a cock’s comb : in ca¬ 
pillary filaments : in radiating fibrous maffes : in all kinds 
of ftalaCtitic (hapes: in the form of l'mall muflirooms: in 
rounded nodules, which from the roughnels of their fur- 
face have been compared to mulberries; this roughnefs 
being occafioned by the projecting points of imall crydals 
cludered together : fometimes in maffes in which the dif- 
tribution of the feveral parts prefents an appearance (imi > 
lar to fome varieties of agate, particularly that called 
fortification - 
