494 Metals. MINER 
real metal. Fig. 2 is another piece of native copper from 
Hungary, fuperficially covered with fpangles of gold and 
mountain-green. As gold is fometimes intimately com¬ 
bined with other metals, it is not extraordinary to meet 
with it on the i'urface. Fig. 3 is native copper in ferpen- 
tine-ftone, cut and polilhed. Found near the Lizard, 
Cornwall. Fig. 4. is native copper with green native ver¬ 
digris. A conliderable quantity of this copper was found 
very near the furface of the ground many years fince ; but 
none has been difcovered lately. From Mullion near the 
Lizard. Fig. 5 is red copper-ore, called C. lateritium, or 
tile-ore, formed in bliffers, like cinders, which are broken 
in jfome places, and the copper nearly decompofed and 
converted into copper-ochre, with fome red cryffallized 
copper-ore, covered with malachite. From Tincroft, in 
the parilli of Illogan. Fig. 6 is a piece of copper from 
Japan : like all the copper from that country, it is as red 
as fealing-wax, and very rich in gold. Fig. 7 is an ore of 
hepatic copper, of a brownifh colour with a white fpar, 
and marcafite adhering. It may be obferved, that mar- 
calite, being a fulphurous fubffance, often attaches itfelf, 
in the form of vapour, to other bodies belides Hones and 
metals, imparting to them a ffiining yellow glols, like 
brafs, when perhaps no metal w hatever is prefent. Fig. 8 
is a black vitreous ore of copper; very rich, and the cop¬ 
per extremely fine. This is covered with marcafite, like 
the preceding. * Fig. 9 is a fpecimen of blue copper. This 
is one of the lefs-frequent ores of copper ; it is a quartzofe 
Hone, hard and compact, impregnated with the vapour of 
copper in folution with vitriol. It is fufceptible of a very 
fine polilh ; and has occafionally veins of marcafite, which 
are often miffaken for gold. To the prefent fpecimen, 
which is of an irregular form, is attached fome ffria; of 
mountain-green which looks like fatin ; and hence it is 
called fatin-ore : fome beautiful cryftallizations appear at 
the bafe. Fig. 10 is another of the lefs-frequent ores; 
namely, malachite, or green copper. Its bafe is a fpar, 
not very hard and compact ; colour a fprightly grafs- 
green, often ftriated or fpotted. As this is capable of re¬ 
ceiving a fine polilh, and is belides found more rarely and 
in fmaller pieces than the blue ore, it was formerly ranked 
among the opaque precious Hones; however it is now 
knowm to have no right to be fo confidered, being only a 
Hriated Hone imbued with a green cupreous vapour. 
Fig. 11 reprefents hollow globules or bubbles of green 
copper-ore, like fmall eggs, in the cavity of a Hone of 
quartz. Fig. 12 is a beautiful copper pyrites, containing 
a good deal of fulphur, and, from its varying colours, 
called peacocli s-tail copper , C. pfittacinum. Thefe co¬ 
lours arife no doubt from a peculiar combination of the 
copper with iron, fulphur, and arfenic ; it exhibits indeed 
all the colours of the rainbow. The Hone or earth con¬ 
taining this ore is fpar and lamellar quartz. The habitat 
of this ore is unknown ; it probably comes from Hungary 
or from Saxony. Fig. 13 is an ore of yellow copper, 
C. fulvum. This is the moH common, and, from the ful¬ 
phur it contains, is called cupreous pyrites. This kind of 
pyrites often inclines to green, or is covered with a dirty 
mountain-green, as it were decompofed. The Hone is 
commonly a fpar or a horn-Hone. 
Ferrum, Iron.—Bluifh-grey; eafily rufiing in the air ; 
very hard, tenacious, and elattic ; fbnorous, exceedingly 
malleable, dudlile; attracted by the magnet, and itfelf 
convertible into the magnet; fpecific gravity, 7778. Be¬ 
coming white in the fire, then emitting brilliant lparks, 
and at lafi melting; forming a red oxyd when its filings 
are kept red-hot in an open vefiel and flirred ; foluble in 
all acids, giving them an qffringent tafie and a black co¬ 
lour when mixed with vegetable affringents ; precipitating 
a green powder when diflolved in fulphuric acid and mixed 
with potafli; with the pruffic acid producing a rich azure 
blue. 
The employment of cafi-iron in the conffruflion of 
edifices, firff pra&ifed among ourfelves, (fee Iron, vol. xi. 
p. 378, 9.) feems to be fpreading on the continent; it was 
A L O G Y. Metals. 
lately made the fubjeft of a public difcourfe at a general 
meeting of the Royal Academy of Sciences at Munich. 
The fpeaker was the counfellor Baader, who defcribed in 
firong terms the advantages attending the ufe of this ma¬ 
terial in building. In the mean time, a new application 
of iron in the Hreets of London, has for fome months 
paH excited confiderable attention. Infiead of paving 
them with Hone, it is propofed to employ fquare pieces 
of call-iron, fuitably fliaped,. roughed, and dove-tailed. 
The experiment has already been tried on the fouth 
fide of Blackfriars-bridge; and has fo far fucceeded, 
that we learn it is intended to pave fome Hreets in the 
city in this manner, under the aufpices of the patriotic 
lord-mayor, and to begin with Wood-ftreet. If this plan 
fiiould lucceed, we may congratulate the iron-mafiers and 
their workmen on a new' market for iron. It is com¬ 
puted that an iron pavement, well adjuffed, will endure 
lor twenty years in a great thoroughfare ; whereas, it is 
too well known that a Hone pavement requires repairs 
and re-adjufiing at leaH once in the year, and renewing 
every three or four years. The pieces laid down in Black^ 
friars-road refemble a batch of eight or nine rolls, as 
taken from the oven ; and they are united like the parts of 
a difledled map, without interflices, or even palpable joints. 
During many months, under every kind of load, and the 
roughen ufage, the firmnefs of this mafs has been undif- 
turbed. The next experiment, it is underHood, is to be 
made in Piccadilly : a part of that immenfe thoroughfare, 
from the beginning of the Green Park to Hyde Park, is 
to be paved with call-iron from a foundery in Wales. 
Befides this new and extenfive application of iron, 
another has Hill more recently prefen ted itfelf in the co¬ 
lonnades of the opera-houfe, which, inHead of being com- 
poled of the perilhable materials of Hone, wood, or plaf- 
tered brick, have been caH in iron ; and recommend 
themfelves to admiration, not lefs by their beauty and pre- 
cifion than by the defiance they fet to the ravages of time. 
There are thirty-four fpecies or combinations of iron. 
1. Ferrum nativum, or native iron. The exiltence of 
native iron is not nearly fo quefiionable as of lead and 
tin ; though there is Hill a confiderable difference of opi¬ 
nion on the fubjedl. It is faid to have occurred in the 
form of a vein, mixed with iron-ore, at Eibenffock in 
Saxony; and alfo in the vicinity of Grenoble in Dau- 
phiny ; but, in the greater number of inffances, thofe 
lpecimens which arepreferved in cabinets under the name 
of native iron, have been detached from iniulated mafies 
met with on the furface of the earth. Thefe mafies are 
totally unconnected, not only with the neighbouring fub- 
ffances, but with every mineral hitherto difcovered ; with 
the exception at leaff of certain earthy bodies, found uii' 
der fimilar circumffances, which will be fpoken of under 
the lecond fpecies. 
Mr. Howard (Phil. Tranf. 1788.) ^mentions three dif¬ 
ferent mafies of native iron : one, met with in Siberia; 
another, in Senegal; the third, in South America; the 
laff-mentioned weighs fifteen tons. A mafs of native 
iron has alfo been met with in Croatia. 
The Siberian native iron was difcovered by Pallas : the 
weight of it was equal to 1680 Ruffian pounds. Accord¬ 
ing to his account, the Tartars confider it as a facred relic 
that had dropped from heaven. The ftrudture of this 
fubffance is cellular; in which it correfponds with other 
mafies of native iron; many of the cells have remarkably 
fmooth and poliflied furfaces ; fome of them are filled with 
tranfparent particles of a yellowilh-green colour ; and, as 
thefe particles correfpond in dimenlions and form with 
the cells containing them, and are liable to decompofition, 
it is prefumed that the cells now empty were once occu¬ 
pied by fimilar particles. The internal colour of the na¬ 
tive iron of Siberia is like that of call-iron : it is exter¬ 
nally covered with a thin ochry incruffation, or rather 
fimply a tarnifii, of a yellowilh brown colour. It is very 
malleable ; and may be eafily cut with a knife. Specific 
gravity 6’4-S, which is much below that of forged iron; 
but 
