Juniata sentinel. [volume] (Mifflintown, Pa.) 1846-1873, 1873-09-24
Jef...HOw and Where it is OBJ
tained.

A writer in the Practical Magazine
gives the following interesting particu-
lars regarding jet, material much used
for the manufacture of mourning jew
elry. In this country, we may remark,
the substance is largely initiated by
vulcanized rubber, which, when new,
closely resembles the genuine article.
Real jet jewelry mounted in gold is
worth from five and six to as high as
seventy dollars per set, the price, how
ever, depending principally upon the
quantity of precious metal used. 1t is
very serviceable, and, unlike rubber, it
retains its brilliancy.
Jet is of two distinct species-hard
Jet and soft jet--but the latter is of very
minor importance and will be referred
to hereafter.
The hard Jet is found in the strata
known as the jet rock, which appears to
be deposit of sea anemones, and some
years ago patent was taken out to dis
till petroleum from it.
The jet rock occurs in the has forma-
ton some thirty yards above the main
band of Cleveland ironstone, and is dis
covered in compressed masses in layers
of very different sizes, being generally
from half an inch to two and half
inches in thickness, from fonr to thirty
inches wide, and four or five feet in
length. 1t invariably tapers away, run
ming, as the miners say, to ''feather
edge"
These jet layers are always protected
by skin, the color making another di-
vision; for that found in the cliffs by
the sea has always blue skin, while
that discovered in the inland hills has a
yellow coating. The jet found in the
same mine varies very much in quality;
its worst specimens, those which are
quite brown and will not take polish,
are termed "dazed jet"
The soft jet is confined to the lower
oolite-in the sandstone and shale-
some 160 yards higher than the hard
jet, and is undoubtedly of pure ligne-
Gus origin, the fibre and the branches
of trees being more or less distinctly
marked.
The most valuable finds of jet have
been washed down by the seas action,
where the jet rock crops out in the
cliffs, and on the cliffs where the seams
are exposed. The dealers of the town
of Whitby, in Yorkshire, England, where
the principal deposits of the material
exist, rent these jet cliffs and inland
seams from the owners, generally for a
fixed lump sum paid in advance-not
for royalty-for the right to work a
certain number of yards. Nearly all the
JET now obtained is found inland, but
in former days tales are told of men
being swung by ropes over steep cliffs
like the eider-dOwn hunters of Norway.
At present, cliff jet is worked with the
same mining operations as that lying
under the inland hills.
The process is very simple, anil, to
those acquainted with the intricacies of
iron and coal mining, of no very great
interest. A mine is commenced by
drifting into the face of rock a pass
age of seven feet by five. A tramway is
then laid down, and the shale is tilted
from the mouth of the mine, the drift
continued for about forty yards, at the
rate of from two to four feet per diem;
then cross drifts are started in variety
of directions. As soon as the rock be-
comes too hard, the miners retire, pull
ing in the roofs as they recede, for the
bulk of the jet is found generally in the
falling top rock.
There are at present twenty-three jet
mines in full work, only one of these
being of soft jet. The average number
of men employed in each mine is six,
and there are now some hundred and
fifty miners engaged in this industry.
The men are generally paid by the week,
and only earn from twenty-four to
twenty-six shillings-a sorry contrast
to the high wages of the iron miners.
Hard jet varies in prices from Is cents
to So. so per fb. /; soft jet from $1.37 to
$3.50 per stone, according to size and
quality, and sometimes also according
to the fluctuations of the market. For
instance, when the Prince of Wales life
was in danger, Whitby was thronged
with buyers for both the raw and manu-
factured article at any price, and some
speculators were severely bitten by his
happy recovery.
It Is stated that the turnover in rough
English hard jet amounts to $500, 900
annually.
The material is manufactured as fol-
lows: The Jet il first peeled and stripped
Of its skin, be it blue or yellow, by
means Of manual chipping process
with : heavy iron-handlsd chisel Il is
TIN avn nm inf0 kha axnNk aizan fnr