The Ottawa free trader. [volume] (Ottawa, Ill.) 1843-1916, 1855-12-15

| JeWclry KNOW that thc bright ana DeautlIu
colors exhibited by most of their much pri
zed gems are purely artiiicials Nature sup
plies the raw material, and art steps in t
embellsh it. The brilliant necklace OF
I bracelet, which, with the native hue Of tn,
stone, would by no means be considered or
namental, become matchlcss in tint and lus
tire, after passing through the hands Of the
artiiiccr. Your chemist, always discovering
something, and always ready with marvel
lous transformations, is truly remarkable
parsonage. lie is jealous Of his secrets, bu,
not always able to keep them. If he could
set seal on his doings, our readers would
not have been entertained with the present
article, in which We shall take leave to ve.
veal some Of his processes.
Let US begin with agate-rathcr a com.
mon stone, found almost everywhere, and in
nuInerous varieties. Hmong which srss the
chalccdony, cornelian, onyx, sardonyx, and
heiotrope. They all consist principally OF
quartz, and are more or less pelucid. In
some places they are surprisingly abundant.
One Of these places is Obcrstein, some thir-
ty or forty miles up the valley of the Nahe,
a region not often visited by summer tour.
lists, yet interesting enough to repay him
who shall explore It's devious by-ways and
paths along the river. At the village Just
mentioned, and at Idsl, four miles distant,
formations OF course red conglomerate are
met with, intcrposcd with trap and green.
stone; and in soft stratum in these rocks.
agate are found in considerable quantities.
The workings may indeed be called agate.
quarr!es for they arc carried on in the pre-.
cipitous side oi a hill (; and to him who secs
them for the first time, there is something
remarkable IN the species Of Industry crea-
ted by the presence Of the stones.
The nodulcs Of agate AS they come from
their long undisturbed bed, are generally Of
an ashen gray color. The first operation in
the process Of transformation is to wash
them perfectly clean then TO put them into
vessel containing mixture Of honey and
water, "hich being closely covered, is
plunged INTO hot ashes for two or three
weeks. Inc essential Thing is to keep the
liquid from boiling, but at high ,.mpers.
ture. After a sufficient interval, the sto,..s
are taken out, c!canscd, passed through a
bath Of sulphurc acid, and then they undergo
a second course ofroastug in the hot ashes.
TO produce \ color in the stones, il is neccs.
sary they should be penetrated by some car.
bonisablc sGbgtansc This is effected by the
honey, which, undor the influence Of long
continued heat, finds lis way into the interior
Of the crystal, where its carbonisation, if not
complete in the first instance, is finished by
the sulphuric acid. Some apidarics use
olyeG! instead ei honey. The shade Of color
depends on the porosity Of the layers OF the
stone the most porous become perfectly
black. Some are colorod in two or three
hours others in as many days, others in !
week or two, and some resist all attempts to
change their natural hue. Some, when taken
out of the pan, arc found 10 be rich dark.
brown, or chocolate; others, again, having
been penetrated by the coloring matter be-
tween the layers, are striped alternately
white, gray and brown, like the onyx and sar.
donyX.
BY soaking the stones in solution Of sui
phate Of iron, and then placing them for a
few hours in the oven, fine corncian red
is produced in the porous layers, while
those not porous remain unaltcred. Thus il
not unirequen,ly happens that very coarse
and common stones-muddy yellow or
cloudy gray, which in their natural condi-
ton would be yalueless, are passed of as
stones Of the first quality. 1t is only with
IN the last forty years that this process has
been known in Germany but the Italian
lapdares were acquainted with 1t centuries
ago. Hence We can account for the eNqui-
site color OF antique canoes and other orna-
monts once numerous in the cabinets Of tia
Iy, and now to be seen in museums and pri-
yate collections in all parts of the world.
The dealers, when making their purcha
g c,n lao al
select what appears to be Il desirable piece
aud chipping of a minute portion, they
moisten the exposed surface with The
tongue, and watch the absorption Of the
moisture. IL regular and equal, the stone
is good for an onyx; il not, it is added tC
the heap Of inferior varieties. This, howe
yer, is but a rough and ready test, and not
always decisive.
The pores of the stones by which the co
lor is conveyed and retained, arc visible
with the microscope, and the effect of vari
Gus tnts is produced according as the ligh
falls upon them at different angles. Th,
rainbow agate is full Of minute cells, which
when exposed TO the sun, produce prsmati'
1 colors, as is observed Of the strin Of mo
/ ther.of.pearl. To detect cavities in tht
','",S' '"'' ' ~
slowly pehstfaehe' re'eala Tue ho'o"s
some already contain water when iouhd
and II is remarkable TACT, that II Kept IN
dry place, the water disappears, but with
out leaving tue 81 ghtest trace oil moisture OF
the surface, and the stones can only be re
ii!led by boiling them.
Balls OF striped rcd chaicedony are muc'
priced large one, weighing hundre,
pounds, was found in lS4i near WeisSeI
berg, and was sold IN the rough ior 'o'
snllders. Some kinds oil chaIcedony arr
made to appear OF cl'ron yellow, ny tw'
days roasting in an oven, and suoscqnen
immersion in close hot bath OF spirit o
salt for two or three weeks A blue color
which has all the effect OF turquoise, is al
so produced but tho particular colorlnt
process has hitherto been Kept n secret
Those stones which arc uaturally y coIored art
az ast t,a'S ~ =. ,oaSm m" " Thn mo r az.
"ar -. W .s pv' ,'e,n",'., ~ ,"h a.,
.n. a" o',Ts , ;m ,h,, .uoi ,Io in, ,,'
p,o,S p,;r "o 80, tp""I h.. o.s ."1t ~ a"o ,J,,s
Jv",o as ;r"u $500 " ~ ,ho ,,ona oT
"v !, ,h " "n ,ar .Yvu Tn.n,a ~ tG dso% ,s na ,l,
~ WI . .. nv,