_a._ See _above_ (before 1 _a_.).
_b._ From sulphide of antimony, 100 parts; iron (in very small scraps), 40
parts; dry crude sulphate of soda, 10 parts; powdered charcoal, 2-1/2
parts; fused together.--_Prod._ 60 to 65 parts of antimony, besides the
scoriæ or ash, which is also valuable.
_c._ (Berthier.) Sulphide of antimony, 100 parts; hammerschlag (rough
oxide or iron from the shingling or rolling mills), 60 parts; crude
carbonate or sulphate of soda, 45 to 50 parts; charcoal powder, 10 parts;
as last.--_Prod._ 65 to 70 parts.
_Prop., &c._ Bluish-white, lustrous, with a lamellar texture, and a
crystalline or semi-crystalline fracture, with fern-leaf markings on the
surface, when pure (star antimony); extremely brittle (may be powdered);
imparts brittleness to its alloys (even 1-1000th part added to gold
renders it unfit for the purposes of coinage and the arts); melts at
809-810° Fahr., or just under redness; fumes, boils, and volatilises at a
white heat, and, when suddenly exposed to the air, inflames with
conversion into the teroxide, which is deposited in beautiful flowers or
crystals; when perfectly pure and fused without contact with air or
foreign matter, it bears an intense heat without subliming (Thénard);
allowed to cool slowly from a state of perfect fusion, it crystallises in
octahedrons or dodecahedrons; tarnishes, but does not rust by exposure to
air or moisture at common temperatures; hot hydrochloric acid dissolves
it, with the formation of TRICHLORIDE OF ANTIMONY; nitric acid, when
concentrated, converts it into ANTIMONIC ACID; and when dilute, into
TRIOXIDE OF ANTIMONY. Sp. gr. 6·7 to 6·8.[69]
[Footnote 69: When perfectly pure, 6715--Ure.]
_Tests._ Metallic antimony may be recognised by the above properties; its
oxide, salts, &c., by the following reactions:--1. Sulphuretted hydrogen
gives, with acid solutions, an orange-red precipitate, which is sparingly
soluble in ammonia,[70] and insoluble in dilute acids; but readily soluble
in pure potassa and alkaline sulphides, and in hot hydrochloric acid with
the evolution of sulphuretted hydrogen gas:--2. Sulphydrate of ammonium
gives an orange-red precipitate, readily soluble in excess of the
precipitant, if this latter contains sulphur in excess; and the liquor
containing the re-dissolved precipitate gives a yellow or orange-yellow
precipitate on the addition of an acid:--3. Ammonia and potassa, and their
carbonates, give (except in solutions of tartar emetic) a bulky white
precipitate; that with ammonia and its carbonate being insoluble in excess
of the precipitant; that with potassa, readily so; whilst that with
carbonate of potassium is only soluble on the application of heat:--4. A
rod of zinc throws down metallic antimony, as a black powder, from all its
solutions not containing free nitric acid. If the experiment be made with
a few drops of a solution of antimony containing a little free
hydrochloric acid, and a small platinum dish or capsule be employed, the
part covered by the liquid is soon stained brown or blackish, and the
stain is irremovable by cold hydrochloric acid, but may be easily removed
by warm nitric acid:--5. By ebullition of the acidulated liquid along with
copper gauze, foil, or wire, as noticed under 'Reinsch's Test.'[71] The
peculiar violet-grey of the deposit is characteristic, and may easily be
distinguished from that given by arsenical solutions:--6. Mixed with
dilute sulphuric acid and poured on some metallic zinc in a gas-generating
flask, provided with a small bent tube (see _engr._), it yields
ANTIMONETTED HYDROGEN (Marsh's test), recognised by burning with a
bluish-green flame, and furnishing dense white fumes which adhere readily
to any cold substance (as a porcelain plate) held over it; or, if the
plate be depressed upon the flame, a deep black, and almost lustreless
spot of metallic antimony; the fumes and spots in both cases being
insoluble in water, and in dilute solution of chloride (crude
hypochlorite) of soda. On heating the centre of the tube to redness with a
spirit lamp, the bluish-green colour of the flame lessens in intensity,
and a mirror of metallic antimony, of silvery lustre, forms inside the
tube at the ignited part. On passing dry sulphuretted hydrogen through the
tube, still heated by a spirit lamp, this mirror assumes a reddish-yellow
colour, approaching black in its thicker parts; and by exposure to a
feeble stream of hydrochloric acid gas, almost immediately, or in a few
seconds, disappears, being carried off by the gas, which, if passed into a
little distilled water, yields a solution of chloride of antimony, which
may be further submitted to any of the usual tests.[71] If the substance
be in the solid state, it must be reduced to powder and dissolved in
water; or if insoluble in that menstruum, a solution must be obtained by
digestion in either hot hydrochloric or nitrohydrochloric acid, before
proceeding to examine it by this method.
[Footnote 70: The like precipitate from a solution of antimonic acid in
hydrochloric acid, dissolves readily in ammonia, particularly when
heated.]
[Footnote 71: See ARSENIOUS ACID.]
[Illustration:
_a_, Flask containing the suspected fluid, dilute sulphuric acid,
and zinc.
_b_, Small tube, at the one end having an almost capillary
orifice, where the gas is inflamed.
_c_, Spirit-lamp.
_d_, Support.]
_Estim._ Antimony is generally WEIGHED under the form of tersulphide; but
sometimes as antimonious anhydride, and--though more seldom--as pure
metal:--
1. A solution being obtained as above, if necessary, it is strongly
acidulated with tartaric acid, and the antimony thrown down as a sulphide
by a stream of sulphuretted hydrogen. After warming the solution and
allowing it to cool, the precipitate (TERSULPHIDE) is collected on a
filter, dried, and weighed. A small portion digested in strong
hydrochloric acid will completely dissolve if it be the pure sulphide; in
which case the quantity of ANTIMONY sought will be equal to 71-1/2%
(71·5%) of the weight of the sulphide found (very nearly).[72] Should only
part of the precipitate be soluble, a known weight of it may be introduced
into a flask, and a considerable quantity of fuming nitric acid added,
drop by drop, and afterwards, a little hydrochloric acid, the mixture
being digested, at a gentle heat, until the reaction is complete, and the
whole of the sulphur is dissolved. The resulting solution diluted with
water, strongly acidulated with tartaric acid, and solution of chloride of
barium added as long as it disturbs the liquid, yields a precipitate, of
which the weight, after it has been thoroughly washed, dried, and gently
ignited, multiplied by 136, gives the quantity of SULPHUR in the sample;
and which, deducted from the weight of the sulphide first found, gives the
quantity of pure ANTIMONY, as before.
[Footnote 72: Tersulphide of antimony dried at 212° Fahr. still retains
traces of water, which is not wholly expelled until the heat reaches
390-392°, when it acquires a black colour and a crystalline appearance.]
2. The quantity of PURE ANTIMONY in commercial samples may be determined
by treating them (in powder) with nitric acid, which oxidises the antimony
and leaves it in an insoluble state, whilst it dissolves the other metals.
The resulting oxide is collected on a filter, washed, dried, ignited in an
open porcelain crucible, and weighed--its weight multiplied by ·7898 gives
the quantity of pure metal sought.
3. Dissolve a known weight of the sample in hydrochloric acid, immerse a
blade of pure metallic tin in the solution, and keep the liquor acidulous,
and in a state of gentle ebullition by the heat of a sand bath, when the
whole of the ANTIMONY will be precipitated under the form of a black
powder, and may be collected, washed, dried, and weighed. This is
particularly adapted to alloys of antimony and tin. See _Tests_ (above)
and _Pur._ (below).
_Pur._ The antimony of commerce generally contains a little arsenic, with
variable quantities of iron, lead, sulphur, and tin. These impurities may
be thus detected:--
1. (Arsenic.) By fusing the sample, in powder, mixed with about an equal
weight of tartrate or bitartrate of potassium, in a covered crucible, for
2 or 3 hours, and placing the resulting button, which is an alloy of
antimony and potassium, in a 'Marsh's apparatus' along with a little
water, when the disengagement of hydrogen gas will commence, and may be
tested in the usual manner. See ARSENIC.
2. (Iron.) Dissolve the powdered sample in nitrohydrochloric acid, dilute
the solution with a large quantity of cold water, filter, and pass a
current of sulphuretted hydrogen through the filtrate as long as it
produces a precipitate; again filter, boil the filtered liquor for a few
minutes to drive off the sulphuretted hydrogen, and then test it with
ferrocyanide of potassium, which will give a blue precipitate if iron be
present; or supersaturate the last filtrate with ammonia, and then add
hydrosulphydrate of ammonium, when, under like conditions, a black
precipitate will be formed.
3. (Lead.) Digest the powdered sample in hot nitric acid, which will
dissolve out the LEAD but leave the antimony behind. The whitish powdery
residuum may be washed, dried, ignited, and weighed, as above; the clear
decanted liquor may now be mixed with the first washings, evaporated to
dryness, the residuum re-dissolved in water, and the solution submitted to
reagents (see LEAD). If lead is found to be present, a solution of
sulphate of sodium may be added until it ceases to disturb the liquid, and
the resulting precipitate (sulphate of lead) washed, dried, and gently
ignited (alone) in a porcelain crucible; the weight of the ignited
residuum furnishes a number which, multiplied by ·683, gives the weight of
the LEAD sought.
4. (Sulphur.) The solution in nitrohydrochloric acid, when tested with
either nitrate or chloride of barium, gives a white precipitate of
sulphate of barium, insoluble in both water and acids, which when dried,
ignited, and weighed, and the weight multiplied by ·136, gives the
quantity of SULPHUR as before. In this case, as with the sulphides (see
_above_), free sulphur maybe removed by digesting and washing the powdered
sample in bisulphide of carbon, previous to its solution in the acid, by
which the violence of the subsequent reaction will be lessened.
5. (Tin.) Two samples of equal weight are taken; the one is tested for
ANTIMONY, as described above; the other is dissolved in a mixture of equal
parts of hydrochloric and nitrohydrochloric acid, and a blade of zinc
immersed in the solution (see _above_); the mixed precipitate of tin and
antimony which forms is collected on a weighed filter, washed, dried, and
weighed. The weight of antimony in the first sample subtracted from that
now obtained, leaves a remainder which indicates the quantity of TIN in
the original sample.
_Phys. eff., &c._ Nearly all the salts and preparations of antimony are
emetic and cathartic, and in large doses poisonous--occasioning vomiting,
profuse alvine dejections, acute colic, and inflammation of the stomach
and bowels, often serious, though rarely resulting in death. TARTAR EMETIC
and BUTTER OF ANTIMONY are those from which accidents have principally
occurred.--_Ant., &c._ Copious vomiting, if it has not already occurred,
should be promoted, and the recently prepared hydrated sulphide of iron
administered in considerable doses, followed or accompanied by
mucilaginous drinks and diuretics. If much prostration follows, wine and
stimulants may be had recourse to. In the absence of hydrated sulphide of
iron, a solution of tannin, or decoction of galls; cinchona, or oak bark,
or even powdered cinchona, mixed with tepid water, may be administered.
_Uses._ In the _arts_, antimony enters into the composition of several
useful alloys, as TYPE-METAL, PEWTER, BRITANNIA-METAL, MUSIC-PLATE METAL,
&c. It is added to the alloy for concave mirrors, to give them a finer
texture; to bell metal, to render it more sonorous; and to various other
metals to increase their hardness and fusibility; for the latter purpose
it is employed in the casting of cannon balls.
_Concluding Remarks._ In 'roasting' or oxidising the native sulphide of
antimony on the bed of the reverberatory furnace, as in the common method
before referred to, care must be taken to regulate and gradually raise the
heat, which, until towards the end of the process, need not be extreme,
and then only should it approach dull redness. Without this precaution
much of the undecomposed sulphide will be lost by volatilisation. During
the whole time the 'charge' should also be well stirred with an iron
spatula, to ensure the constant exposure of every part of it to the
atmosphere. The process is complete when the whole mass assumes a
greyish-white appearance. Earthen crucibles are commonly employed for the
subsequent reduction, and after being charged and covered over with ground
charcoal, are heated in a reverberatory furnace. The product is the crude
metallic antimony of commerce. It is generally REFINED by smelting it with
about 1-8th of its weight of the refined sulphide, and about 1-4th of its
weight of carbonate or sulphate of soda; but if there be much iron
present, more of the sulphide--even 1-4th--may be required; for unless
there be sufficient sulphur to combine with the whole of the iron, the
arsenic will not be oxidised, but remain as a contamination. When cold,
the metal is carefully separated from the slag, and is frequently re-fused
with a little fresh carbonate of soda (1 to 1-1/2 part); after which it is
cast into pigs, lumps, or ingots. The crude metal, thus treated, commonly
yields 94% of REFINED METAL of tolerable purity.
Should lead have been present in the sulphide or ore, it remains after a
second, or even a third fusion, although proportionately reduced in
quantity; and it can only be completely separated in the humid way. It is,
therefore, always desirable to select an ore free from lead.
=Antimony, Ash of.= _Syn._ ANTIMONY-ASH, CALCINED' ANTIMONY*; CI'NIS
ANTIMO''NII, ANTIMO''NIUM CALCINA'TUM*, L. Prepared by roasting the common
grey sulphide of antimony on an iron plate set under a chimney, to carry
off the fumes. The product is a mixture of teroxide of antimony, with some
unburnt sulphide, and a little antimonious acid.
_Prop., &c._ Ash-grey; emetic in small doses. Used chiefly as a cheap
substitute for teroxide of antimony by the manufacturers of tartar emetic;
also to make metallic antimony.
=Antimony, Butt'er of.= See ANTIMONY, TRICHLORIDE OF.
=Antimony, Calx of.= _Syn._ CALX ANTIMO''NII, L. Sometimes applied to
antimony-ash, but more commonly to crude, unwashed diaphoretic antimony.
=Antimony, Calx of= (Sul'phurated). _Syn._ ANTIMO''NII CALX SULPHURA'TA,
L. _Prep._ (Hufeland.) Calcined oyster-shells, 10 parts; sulphur, 4 parts;
crude antimony, 3 parts; powder, mix, and calcine in a luted crucible for
an hour. Emetic, resolvent, and alterative.--_Dose_, 1 to 6 gr.; in gout,
rheumatism, scrofula, &c.
=Antimony, Ce'ruse of.= _Syn._ ANTIMO''NII CERUS'SA, L. _Prep._ (Bate.) As
diaphoretic antimony (over which it possesses no advantage), merely using
the metal instead of the sulphide.
An old preparation made by igniting antimony in the sun's rays, by means
of a lens, was called ANTIMONII CERUSSA SOLA''RIS.
=Antimony, Chlo''rides of= (kl[=o]re'-[=i]dz):--
=1. Antimony, Trichloride of.= SbCl_{2}. _Syn._ TERCHLORIDE OF ANTIMONY,
ANTIMONIOUS CHLORIDE, CHLO''RIDE OF ANTIMONY, SESQUICHLORIDE OF A., BUTTER
OF A., CAU'STIC ANTIMONY[dagger], &c.; ANTIMO''NII CHLORI'DUM, A.
TERCHLORI'DUM, A. BU'TYRUM*, &c., L.; CHLORURE D'ANTIMOINE, BEURRE
D'ANTIMOINE, &c., Fr.; ANTIMON-CHLORID, SPIESSGLANZ-BUTTER, Ger. This is
the substance of which common chloride, or butter of antimony, of the
shops, is an impure concentrated solution containing free acid.
_Prep._ 1. SOLID, ANHYDROUS:--
_a._ Pure commercial tersulphide of antimony, in coarse powder, 1 part;
concentrated hydrochloric acid, 5 parts; are mixed in a capacious
stoneware or glass vessel set under a chimney with a quick draught, to
convey away the fumes, the whole being constantly stirred, and, as the
effervescence slackens, a gradually increasing gentle heat applied until
solution is complete; the resulting liquid is put into a retort, and
distilled, until each drop of the distillate, as it falls into the aqueous
liquid which has previously passed over into the receiver, produces a
copious white precipitate; the receiver is then changed, and the
distillation continued, when pure TRICHLORIDE OF ANTIMONY passes over, and
solidifies on cooling to a white and highly crystalline mass, which must
be carefully excluded from the air.
_b._ From pure metallic antimony, 2 parts; bichloride of mercury, 5 parts;
both in fine powder; mixed and distilled in a retort with a large neck, by
a gentle sand-heat, into a suitable receiver. Chemically pure.