«Ivory»
(See also Bones, Shell, and Horn.)
«TO COLOR IVORY:»
Red.—The article is placed for 24 hours in water, 1,000 parts of which
carry 100 parts of vinegar (acetic acid, 6 per cent), and from 1 to 5
parts of aniline red. As soon as it acquires the desired color pour off
the liquid, let the ivory dry, and polish with Vienna lime.
Black.—Wash the article first in potash or soda lye and then put into a
neutral solution of silver nitrate. Drain off the liquid and lay in the
direct sunshine.
Red-Purple.—Put the article in a weak solution of triple gold chloride
and then into direct sunshine.
Red.—For a different shade of red (from the first given), place the
article for a short time in water weakly acidified with nitric acid and
then in a solution of cochineal in ammonia.
Yellow.—Leave for several hours in a solution of lead acetate, rinse
and dry. When quite dry place in a solution of potassium chromate.
To Color Billiard Balls Red.—
_Fiery Red._—Wash the article first in a solution of carbonate of soda,
then plunge for a few seconds in a bath of equal parts of water and
nitric acid. Remove, rinse in running water; then put in an alcoholic
solution of fuchsine and let it remain until it is the required color.
_Cherry Red._—Clean by washing in the sodium carbonate solution, rinse
and lay in a 2 per cent solution of tin chloride, for a few moments,
then boil in a solution of logwood. Finally lay in a solution of
potassium carbonate until it assumes the desired color.
_Pale Red._—Wash in soda solution, rinse and lay for 25 minutes in a 5
per cent solution of nitric acid, rinse, then lay for several minutes
in a weak solution of tin chloride. Finally boil in the following
solution: Carmine, 2 parts; sodium carbonate, 12 parts; water, 200
parts; acetic acid enough to saturate.
_Brown._—Apply several coats of an ammoniacal solution of potassium
permanganate. Similar results are obtained if the solution is diluted
with vinegar, and the ivory article allowed to remain in the liquid for
some time.
«Etching on Ivory» (see also Etching).—Although decorations on ivory
articles, such as umbrella handles, cuff-buttons, fans, book-covers,
boxes, etc., are generally engraved, the work is frequently done by
etching. The patterns must be very delicate, and are executed in lines
only. The simplest way is to cover the surface with a thin rosin
varnish. Then transfer the pattern and scratch it out accurately with
a pointed needle. Otherwise proceed same as in etching on metal and
stone, making an edge of modeling wax around the surface to be etched
and pouring on the acid, which consists, in this case, of sulphuric
acid, 1 part, to which 5 to 6 parts of water are added. It acts very
quickly. The lines turn a deep black. If brown lines are desired,
dissolve 1 part of silver nitrate in 5 parts of water, etch for a
short time, and expose the article for a few hours to the light, until
the design turns brown. Very often etchings in ivory are gilded. For
this purpose, fill the etched patterns accurately with siccatives,
using a writing pen, dry, and dab on gold leaf. After a few hours
remove the superfluous gold with wadding, and the design will be nicely
gilded. Etched ivory articles present a very handsome appearance if
they are first covered with a silvery gloss, the design being gilded
afterwards. For the former purpose the etched object is laid in the
above described solution of silver nitrate until it has acquired a dark
yellow color. Then rinse it off in clean water and, while still moist,
expose to direct sunlight. After 3 to 4 hours the surface becomes
entirely black, but will take on a fine silvery luster if rubbed with
soft leather.
«Flexible Ivory.»—To soften ivory and render it flexible put pure
phosphoric acid (specific gravity, 1.13) into a wide-mouthed bottle or
jar that can be covered, and steep the ivory in this until it partially
loses its opacity; then wash the ivory in cold, soft water and dry,
when the ivory will be found soft and flexible. {429} It regains its
hardness in course of time when freely exposed to air, although its
flexibility can be restored by immersing the ivory in hot water.
Another softening fluid is prepared by mixing 1 ounce of spirit of
niter with 5 ounces of water and steeping the ivory in the fluid for 4
or 5 days.
«Hardened Ivory.»—To restore the hardness to ivory that has been
softened by the above methods, wrap it in a sheet of white writing
paper, cover it with dry decrepitated salt, and let it remain thus
covered for 24 hours. The decrepitated salt is prepared by strewing
common kitchen salt on a plate or dish and standing same before a
fierce fire, when the salt loses its crystalline appearance and assumes
a dense opaque whiteness.
«IMITATION IVORY:»
See also Casein and Plaster.
Manufacture of Compounds Imitating Ivory, Shell, etc.—Casein, as known,
may act the part of an acid and combine with bases to form caseinates
or caseates; among these compounds, caseinates of potash, of soda, and
of ammonia are the only ones soluble in water; all the others are
insoluble and may be readily prepared by double decomposition. Thus,
for example, to obtain caseinate of alumina, it is sufficient to add to
a solution of casein in caustic soda a solution of sulphate of alumina;
an insoluble precipitate of casein, or caseinate of alumina, is
instantly formed. This precipitate ought to be freed from the sulphate
of soda (formed by double decomposition) by means of prolonged washing.
When pure, ordinary cellulose may be incorporated with it by this
process, producing a new compound, cheaper than pure cellulose,
although possessing the same properties, and capable of replacing
it in all its applications. According to the results desired, in
transparency, color, hardness, etc., the most suitable caseinate should
be selected. Thus, if a translucent compound is to be obtained, the
caseinate of alumina yields the best. If a white compound is desired,
the caseinate of zinc or of magnesia should be chosen; and for colored
products the caseinates of iron, copper, and nickel will give varied
tints.
The process employed for the new products, with a base of celluloid and
caseinate, is as follows: On one hand casein is dissolved in a solution
of caustic soda (100 of water for 10 to 25 of soda), and this liquid is
filtered, to separate the matters not dissolved and the impurities.
On the other hand, a salt (of the base of which the caseinate is
desired) is dissolved, and the solution filtered. It is well not to
operate on too concentrated a solution. The two solutions are mixed in
a reservoir furnished with a mechanical stirrer, in order to obtain
the insoluble caseinate precipitate in as finely divided a state as
possible. This precipitate should be washed thoroughly so as to free it
from the soda salt formed by double decomposition, but on account of
its gummy or pasty state, this washing presents certain difficulties,
and should be done carefully. After the washing it should be freed from
the greater part of water contained by draining, followed by drying,
or energetic pressing; then it is washed in alcohol, dried or pressed
again, and is ready to be incorporated in the mass of the celluloid.
For the latter immersion and washing, it has been found that an
addition of 1 to 5 per cent of borax is advantageous, for it renders
the mass more plastic, and facilitates the operation of mixing. This
may be conducted in a mixing apparatus; but, in practice, it is found
preferable to effect it with a rolling mill, operated as follows:
The nitro-cellulose is introduced in the plastic state, and moistened
with a solution of camphor in alcohol (40 to 50 parts of camphor in
50 to 70 parts of alcohol for 100 parts of nitro-cellulose) as it is
practiced in celluloid factories.
This plastic mass of nitro-cellulose is placed in a rolling mill,
the cylinders of which are slightly heated at the same time as the
caseinate, prepared as above; then the whole mass is worked by the
cylinders until the mixture of the two is perfectly homogeneous, and
the final mass is sufficiently hard to be drawn out in leaves in the
same way as practiced for pure celluloid. These leaves are placed in
hydraulic presses, where they are compressed, first hot, then cold, and
the block thus formed is afterwards cut into leaves of the thickness
desired. These leaves are dried in an apparatus in the same way as
ordinary celluloid. The product resembles celluloid, and has all its
properties. At 195° to 215° F. it becomes quite plastic, and is easily
molded. It may be sawed, filed, turned, and carved without difficulty,
and takes on a superb polish. It burns less readily than celluloid,
and its combustibility diminishes in proportion as the percentage of
caseinate increases; finally, the cost price is less than that of
celluloid, {430} and by using a large proportion of caseinate, products
may be manufactured at an extremely low cost.
«IVORY AND BONE BLEACHES.»
If simply dirty, scrub with soap and tepid water, using an old tooth
or nail brush for the purpose. Grease stains may be sometimes removed
by applying a paste of chalk or whiting and benzol, covering the
article so that the benzol may not dry too rapidly. Carbon disulphide
(the purified article) may be used in place of benzol. When dry, rub
off with a stiff brush. If not removed with the first application,
repeat the process. Delicately carved articles that show a tendency
to brittleness should be soaked for a short time in dilute phosphoric
acid before any attempt to clean them is made. This renders the minuter
portions almost ductile, and prevents their breaking under cleaning.
The large scratched brush should be treated as follows: If the
scratches are deep, the surface may be carefully rubbed down to the
depth of the scratch, using the finest emery cloth, until the depth is
nearly reached, then substituting crocus cloth.
To restore the polish nothing is superior to the genuine German putz
pomade, following by rubbing first with chamois and finishing off with
soft old silk. The more “elbow grease” put into the rubbing the easier
the task, as the heat generated by friction seems to lend a sort of
ductility to the surface. To remove the yellow hue due to age, proceed
as follows: Make a little tripod with wire, to hold the object a few
inches above a little vessel containing lime chloride moistened with
hydrochloric acid; put the object on the stand, cover the whole with a
bell glass, and expose to direct sunlight. When bleached, remove and
wash in a solution of sodium bicarbonate, rinse in clear water and dry.
Like mother-of-pearl, ivory is readily cleaned by dipping in a bath of
oxygenized water or immersing for 15 minutes in spirits of turpentine,
and subsequently exposing to the sun for 3 or 4 days. For a simple
cleaning of smooth articles, wash them in hot water, in which there
has been previously dissolved 100 parts (by weight) of bicarbonate of
soda per 1,000 parts of water. To clean carved ivory make a paste of
very fine, damp sawdust, and put on this the juice of 1 or 2 lemons,
according to the article to be treated. Now apply a layer of this
sawdust on the ivory, and when dry brush it off and rub the object with
a chamois.
«IVORY TESTS.»
Many years ago an article was introduced in the industrial world which
in contradistinction to the genuine animal ivory, has its origin in
the vegetable kingdom, being derived from the nut of a palm-like shrub
called phytelephasmacrocarpa, whose fruit reaches the size of an apple.
This fruit has a very white, exceedingly hard kernel which can be
worked like ivory. A hundred of these fruits only costing about $1,
their use offers great advantages. Worked on the lathe this ivory can
be passed off as the genuine article, it being so much like it that
it is often sold at the same price. It can also be colored just like
genuine ivory.
To distinguish the two varieties of ivory, the following method may be
employed: Concentrated sulphuric acid applied to vegetable ivory will
cause a pink coloring in about 10 or 12 minutes, which can be removed
again by washing with water. Applied on genuine ivory, this acid does
not affect it in any manner.
IVORY BLACK: See Bone Black.
IVORY CEMENT: See Adhesives.
IVORY GILDING: See Plating.
IVORY POLISHES: See Polishes.
JAPAN BLACK: See Paints.
JAPANNING AND JAPAN TINNING: See Varnishes.
JASMINE MILK: See Cosmetics.
JELLY (FRUIT) EXTRACT: See Essences and Extracts.
JEWELERS’ CEMENTS: See Adhesives.
JEWELERS’ CLEANING PROCESSES: See Cleaning Preparations and Methods.
«Jewelers’ Formulas»
(See also Gems, Gold, and Watchmakers’ Recipes.)
«Coloring Gold Jewelry.»—Following are several recipes for coloring:
Saltpeter, 40 parts; alum, 30 parts; sea salt, 30 parts; or, liquid
ammonia, 100 parts; sea salt, 3 parts; water, 100 parts. Heat without
allowing to boil and plunge {431} the objects into it for 2 or 3
minutes, stirring constantly; rinse in alum water and then in clean
water. Another recipe: Calcium bromide, 100 parts; bromine, 5 parts.
Place the articles in this solution, with stirring, for 2 to 3 minutes;
next wash in a solution of hyposulphite of sodium and rinse in clean
water. Another: Verdigris, 30 parts; sea salt, 30 parts; blood stone,
30 parts; sal ammoniac, 30 parts; alum, 5 parts. Grind all and stir
with strong vinegar; or, verdigris, 100 parts; hydrochlorate of
ammonia, 100 parts; saltpeter, 65 parts; copper filings, 40 parts. Bray
all and mix with strong vinegar.
«To Widen a Jewel Hole.»—Chuck the hole in a lathe with cement. Place a
spirit lamp underneath to prevent the cement from hardening. Hold the
pointed bit against the hole, while the lathe is running, until the
hole is true, when the lamp should be removed. The broach to widen the
hole should be made of copper, of the required size and shape, and the
point, after being oiled, should be rolled in diamond dust until it
is entirely covered. The diamond dust should then be beaten in with a
burnisher, using very light blows so as not to bruise the broach. After
the hole is widened as desired, it requires polishing with a broach
made of ivory and used with oil and the finest diamond dust, loose,
not driven into the broach.
«To Clean Jet Jewelry.»—Reduce bread crumbs into small particles, and
introduce into all the curves and hollows of the jewelry, while rubbing
with a flannel.
«Coloring Common Gold.»—In coloring gold below 18 carat, the following
mixture may be used with success, and if carefully employed, even 12
carat gold may be colored by it: Take nitrate of potassa (saltpeter),
4 parts, by weight; alum, 2 parts; and common salt, 2 parts. Add
sufficient warm water to mix the ingredients into a thin paste; place
the mixture in a small pipkin or crucible and allow to boil. The
article to be colored should be suspended by a wire and dipped into
the mixture, where it should remain from 10 to 20 minutes. The article
should then be removed and well rinsed in hot water, when it must be
scratch brushed, again rinsed and returned to the coloring salts for
a few minutes; it is then to be again rinsed in hot water, scratch
brushed, and finally brushed with soap and hot water, rinsed in hot
water, and placed in boxwood sawdust. The object being merely to remove
the alloy, as soon as the article has acquired the proper color of fine
gold it may be considered sufficiently acted upon by the above mixture.
The coloring salts should not be used for gold of a lower standard than
12 carat, and, even for this quality of gold, some care must be taken
when the articles are of a very slight make.
«Shades of Red, etc., on Matt Gold Bijouterie.»—For the production of
the red and other shades on matt gold articles, the so-called gold
varnishes are employed, which consist of shellac dissolved in alcohol
and are colored with gum rosins. Thus a handsome golden yellow is
obtained from shellac, 35 parts; seed-lac, 35 parts; dragon’s blood, 50
parts; gamboge, 50 parts; dissolved in 400 parts of alcohol; the clear
solution is decanted and mixed with 75 parts of Venice turpentine. By
changing the amounts of the coloring rosins, shades from bright gold
yellow to copper color are obtained. The varnish is applied evenly
and after drying is wiped off from the raised portions of the article
by means of a pad of wadding dipped into alcohol, whereby a handsome
patination effect is produced, since the lacquer remains in the
cavities. Chased articles are simply rubbed with earth colors ground
into a paste with turpentine oil, for which purpose burnt sienna, fine
ochers of a golden color, golden yellow, and various shades of green
are employed.
I.—Yellow wax 32 parts
Red bole 3 parts
Crystallized verdigris 2 parts
Alum 2 parts
II.—Yellow wax 95 parts
Red bole 64 parts
Colcothar 2 parts
Crystallized verdigris 32 parts
Copper ashes 20 parts
Zinc vitriol 32 parts
Green vitriol 16 parts
Borax 1 part
The wax is melted and the finely powdered chemicals are stirred in,
in rotation. If the gilt bronze goods are to obtain a lustrous orange
shade, apply a mixture of ferric oxide, alum, cooking salt, and vinegar
in the heated articles by means of a brush, heating to about 266° F.
until the shade commences to turn black and water sprinkled on will
evaporate with a hissing sound, then cool in water, dip in a mixture of
1 part of nitric acid with 40 parts of water, rinse {432} thoroughly,
dry, and polish. For the production of a pale-gold shade use a wax
preparation consisting of:
III.—Yellow wax 19 parts
Zinc vitriol 10 parts
Burnt borax 3 parts
Green-gold color is produced by a mixture of:
IV.—Saltpeter 6 parts
Green vitriol 2 parts
Zinc vitriol 1 part
Alum 1 part
«To Matt Gilt Articles.»—If it is desired to matt gilt articles partly
or entirely, the portions which are to remain burnished are covered
with a mixture of chalk, sugar, and mucilage, heating until this
“stopping-off” covering shows a black color. On the places not covered
apply a matting powder consisting of:
Saltpeter 40 parts
Alum 25 parts
Cooking salt 35 parts
Heat the objects to about 608° F., whereby the powder is melted and
acquires the consistency of a thin paste. In case of too high a
temperature decomposition will set in.
«To Find the Number of Carats.»—To find the number of carats of gold
in an object, first weigh the gold and mix with seven times its weight
in silver. This alloy is beaten into thin leaves, and nitric acid is
added; this dissolves the silver and copper. The remainder (gold) is
then fused and weighed; by comparing the first and last weights the
number of carats of pure gold is found. To check repeat several times.
«Acid Test for Gold.»—The ordinary ready method of ascertaining whether
a piece of jewelry is made of gold consists in touching it with a glass
stopper wetted with nitric acid, which leaves gold untouched, but
colors base alloys blue from the formation of nitrate of copper.
«Imitation Diamonds.»—I.—Minium, 75 parts (by weight); washed white
sand, 50 parts; calcined potash, 18 parts; calcined borax, 6 parts;
bioxide of arsenic, 1 part. The sand must be washed in hydrochloric
acid and then several times in clean water. The specific gravity of
this crystal glass is almost the same as that of the diamond.
II.—Washed white sand, 100 parts (by weight): minium, 35 parts;
calcined potash, 25 parts; calcined borax, 20 parts; nitrate of potash
(crystals), 10 parts; peroxide of manganese, 5 parts. The sand must be
washed as above stated.
«Diamantine.»—This substance consists of crystallized boron, the basis
of borax. By melting 100 parts of boracic acid and 80 parts of aluminum
crystals is obtained the so-called bort, which even attacks diamond.
The diamantine of commerce is not so hard.
«To Refine Board Sweepings.»—The residue resulting from a jobbing
jeweler’s business, such as board sweepings and other residuum, which
is continually accumulating and which invariably consists of all mixed
qualities of standard, may have the precious metals recovered therefrom
in a very simple manner, as follows: Collect the residue and burn it
in an iron ladle or pan, until all grease or other organic matter is
destroyed. When cool mix with 1/5 part soda-ash, and melt in a clay
crucible. When the metal is thoroughly melted it will leave the flux
and sink to the bottom of the crucible; at this stage the flux assumes
the appearance of a thin fluid, and then is the time to withdraw the
pot from the fire. The metal in the crucible—but not the flux—may now
be poured into a vessel of water, stirring the water in a circular
direction while the metal is being poured in, which causes it to form
into small grains, and so prepares it for the next process. Dissolve
the grains in a mixture of nitric acid and water in equal quantities.
It takes about four times the quantity of liquid as metal to dissolve.
The gold remains undissolved in this mixture, and may be recovered by
filtering or decanting the liquid above it in the dissolving vessel;
it is then dried, mixed with a little flux, and melted in the usual
manner, whereupon pure gold will be obtained. To recover the silver,
dilute the solution which has been withdrawn from the gold with six
times its bulk of water, and add by degrees small quantities of finely
powdered common salt, and this will throw down the silver into a
white, curdy powder of chloride of silver. Continue to add salt until
no cloudiness is observed in the solution, when the water above the
sediment may be poured off; the sediment is next well washed with warm
water several times, then dried and melted in the same manner as the
gold, and you will have a lump of pure silver.
«Restoration of the Color of Turquoises.»—After a certain time
turquoises lose a part of their fine color. It is easy to restore the
color by immersing them in a solution of carbonate of soda. But it
seems that the blue cannot be restored anew after this operation, if it
again becomes dull. The above applies to {433} common turquoises, and
not to those of the Orient, of which the color does not change.
«Colorings for Jewelers’ Work.»—I.—Take 40 parts of saltpeter; 30 parts
of alum; 30 parts of sea salt; or 100 grams of liquid ammonia; 3 parts
sea salt; and 100 parts water. This is heated without bringing it to a
boil, and the articles dipped into it for from 2 to 3 minutes, stirring
the liquid constantly; after this bath they are dipped in alum water
and then thoroughly rinsed in clean water.
II.—One hundred parts of calcium bromide and 2 parts of bromium. The
objects are allowed to remain in this solution (which must be also
constantly stirred) for from 2 to 3 minutes, then washed in a solution
of sodium hyposulphite, after which they must be rinsed in clean water.
III.—Thirty parts of verdigris; 30 parts of sea salt; 30 parts of
hematite; 30 parts of sal ammoniac, and 5 parts of alum. This must be
all ground up together and mixed with strong vinegar; or we may also
use 100 parts of verdigris; 100 parts of hydrochlorate of ammonia; 65
parts of saltpeter, and 40 parts of copper filings, all of which are to
be well mixed with strong vinegar.