IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL MARBLES, GRANITES, AND OTHER STONES
Year: 1876

page_text: LETTERS PATENT to Emile de Laroque, of 24, Leadenhall Street, in the City
of London, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
ARTIFICIAL MARBLES, GRANITES, AND OTHER STONES.”
ealed the 22nd August 1876, and dated the 4th March 1876.
PROVISIONAL SPECIFICATION left by the said Emile de Laroque at the
Office of the Commissioners of Patents on the 4th March 1876.
EMLIE DE LAROQUE, of 24, Leadenhall Street, in the City of London. "IMPROVE-
MENTS IN THE MANUFACTURE OF ARTIFICIAL MARBLES, GRANITES, AND OTHER
STONES."
The object of this Invention is more particularly to give to artificial marbles,
granites, and other stones during their manufacture the necessary colors to
resemble natural marbles and other stones, either veined or otherwise marked.
The following is an example of the ingredients, matters, or substances I propose
to employ in and for the manufacture of marbles, granites, and other stones, and
the manner of operating therewith.
PROCESS OF MANUFACTURE
I propose to make artificial marbles, either in panels, plane or curved mouldings,
columns, statues, and other objects of art and ornament. For this purpose I take
cement produced by combining gypsum with alum, and mixed with pure water or
plaster nixed with gum water, I then take colours (vegetable or mineral) ground
and mixed with water to shade the cement or plaster according to the kind of
marble to be imitated as hereafter described in classification; I also use canvas
or other like material to strenghten the article and proceed as follows:-To produce
marble I commence by mixing with water in a suitable vessel the quantity of cement
or plaster required to make the veined surface of the object about to be made.
The cement or plaster thus mixed I divide in as many basins as may be required,
according to the number of shades of the marble to be made, as hereafter moro
fully indicated. Then on a surface that I call "surface of operations," plane or
curved, on polished glass or other surface polished or non-polished, I trace in the
first instance the veins of the first plan of the marble with silk or other fibres
moistened with coloured water or coloured cement, according to the marble to be

page_text: made, which I will describe in the classification further on; then to form the founda-
tion or rather background of the marble I run the coloured cement or plaster
through the mould, or I place it by hand on the veins traced on the surface of
operations. I make these portions of different density, that is to say, I make the
parts destined to form the veins or the shades, not so thickly mixed as those of the
background so as to produce varied shades and effects, according to the mineralo-
gical and geological order of the marble to be imitated. I make the veined coating
forming the background of the marble about one-tenth of an inch thick, which I
smooth down with a trowel; then, if the veins have been made, with coloured
moistened fibres, I withdraw those fibres from the surface of operation where they
have by their imprint formed the veins of the marble then smooth down a second
time the coating forming the background of the marble, so as to fill up the vacant
space produced by the withdrawal of the fibres; then to prevent air bubbles I stir
for a short time the surface of operation, then withdraw the surplus water I was
obliged to use or mix and colour the cement or plaster forming the veined coating
of the marble by sifting with a sifter a bed of cement or plaster in powder on
the aforesaid background coating. I then withdraw the powdored cement or
plaster a few minutes afterwards, that is to say, when it has absorbed the remainder
of the water, which would prevent this veined coating from hardening; I then
stir the veined coating with a trowel to make it more compact and more adhering
to the lining used for strengthening the article that is to be made, of which I shall
speak later on.
It is to be understood that the side of the coating which I stir with a trowel is
the opposite side to that which is in direct contact with the surface of operations
which is the veined side. To consolidate this slab moulding, or any other article
whatsoever I back it with canvas or other similar material, and then with another
coating of cement or plaster I fasten this canvas with cement or plaster mixed
slightly liquid, so that it adheres to the coating forming the back of the marble;
I then spread on the aforesaid canvas thus fastened on this coating of the back of
the marble another coating of the marble of cement or plaster mixed of the
required thickness, according to the article that is being made (generally about
two-fifths of an inch thick). This last coating of cement or plaster being employed
to consolidate the article that is being made must be mixed with a very small
quantity of water, so as to make a paste of it sufficiently compact, which may be
laid out with a trowel or other similar utensil When this slab moulding or other
article made is crystallized or hardened I take it from the surface of operation or
from the mould which it has been made upon and finish by filling up the pores of
the veined surface of this object, it is then polished with stones and other well-
known ingredients in use for polishing marble.
When the slab moulding or other article made by the foregoing process is to
be used for decorating buildings I attach it to the walls or ceilings thereof by
fixing it with wire hooks which I fasten with cement or plaster, or with screws
or galvanized iron wedged in in wood fastened to the walls or ceilings.
To make any article by the above process in an open or closed mould composed
of several pieces to form, for instance, a column, statue, or the like, I lay out before-
hand all the parts of this mould on a table in such a manner that their ends
correspond, in order that when these parts are united the veins of the marble
formed on each part should be placed according to geological and mineralogical
order of the real marble imitated. On those parts of any mould thus laid out on
a table I form the veined coating the same as if it were on a surface of operation
quite flat, and according to process described above, as also according to the marble
to be produced, as I shall speak of it in the classification of marbles to follow.
When this veined coating is formed and smoothed down after having withdrawn
the surplus water, I put together the parts of the said mould, then the part of the
mould left open, I join together with a spatula, and finish by strengthening the
moulded article as before described with canvas and cement or plaster.
To make articles with various inlaid marbles I make each veined part of these

page_text: marbles separately (and successively on the surface of operation, that is to say
when one part of the veined coating is formed on the surface of operation, and
when the surplus water has been withdrawn by the process described above and
smoothed down, and whilst the cement is still moist I cut out that part with a
knife, according to the inlaying design, and I repeat the same operation separately
for the other parts of the different marbles, until the design is entirely produced,
and I finish the inlaid article by strengthening it with canvas and cement or plaster
as before described.
I now resend to decoribe the alexsifiantion of monbles and the manne at
when one part of the veined coating is formed on the surface of operation, and
when the surplus water has been withdrawn by the process described above and
smoothed down, and whilst the cement is still moist I cut out that part with a
knife, according to the inlaying design, and I repeat the same operation separately
for the other parts of the different marbles, until the design is entirely produced,
and I finish the inlaid article by strengthening it with canvas and cement or plaster
as before described.
I now pressed to describe the classification of marbles and the means of producing
them, respectively as follows:-
WHITE VEINED MARBLE.
To make this marble I commence, as previously described, by mixing in a suitable
vessel the requisite quantity of cement or plaster, according to the size of the
article intended to be made; I then take a sixteenth part of the mixed cement or
plaster, and divide it into five equal parts in five basins; I then color the first of
those five parts with vegetable black, the second with sea blue, the third with
yellow ochre, the fourth with a very small quantity of vermillion, and the fifth
with a small quantity of light citron chrome. These five coloured parts, above-
mentioned, are destined to shade the other parts for the background and the veins
of the marble; I then divide the remainder of the liquid cement or plaster into
three parts, as follows:-The first part, the half of the remaining quantity of liquid
cement; the second, about the quarter; and the third, the remainder of the cement.
The first of these three quantities being required to predominate in the background
of the marble, I shade it lightly with the colouring contained in the first five basins;
I shade the second quantity more deeply than the first, and the third quantity
destined to form the very white shade of the marble. If the cement or plaster is
white enough I leave it its primitive colour, and then with a little of each of these
last three parts, and a little of the first five, I make three distinct shades for the veins.
It is to be understood that I make these shades according to mineralogical order
of the real marble; I make the shades of the background and outer plan of the
marble a little more dense than plaster when cast in a mould, and I make the
shades of the veins less dense than those of the background. I then take a
silk thread from 20 to 28 inches long, and according to the thickness required
for the veins; and, holding this thread by its ends, dip it successively in the
basins containing the shades prepared for the veins. The thread thus dipped is
made to touch the surface of operation in such a way that its imprint shall form a
vein, and I repeat this operation until all the veins of the morble I desire to
produce are traced on the surface of operation. This being done I take another
thread of the same length, but much thicker than the former one, which I dip in
the basin containing the whitest shade, and I make this thread touch the surface of
operation in the same manner as for the veins, in order to form by its imprint the
parts traced lightly, as they are to be found in real white marble. When all the
veins are thus traced I form the outer plan of the marble in colour, or by spreading
by hand on the surface of operation where the veins are already formed the shades
prepared for that purpose, taking care to mix them a little, in order to form plans
and effects of different marbles. Then to form the spotted parts I spread by hand
on the coating forming the background of the marble through a sieve a little
of each shade which has been used for making the veins. I drop these shades with
sufficient force to enable them to go through the coating forming the background of
the marble, and thus arrive at the first plan, and finish as before described.
SIENNA,
To produce this marble I proceed in the following manner:-The quantity of
cement or plaster according to the article to be made, being mixed in the manner
before stated I commence by dividing about the third of this mixed coment ሰ

page_text: citron chrome; the second, with pale orange chrome; the third, with dark orange
chrome; the fourth, with red chrome; the fifth, with laked carmine; the sixth,
with vermillion; the seventh, with tinted sea blue; the eighth, with vegetable
black; and the ninth, destined to form the veins and white knots, must be tinted
slightly with blue, slightly with black, and slightly with light citron chrome. I
then divide the remainder of the mixed cement or plaster into three equal parts, and
give them three different shades according to the marble to be made, light or dark,
with ordinary sienna carth, a little burned sienna earth, and a little of each colour
contained in the first six basins. Then to form the veins of the first plan I take
two basins containing a sufficient quantity of water; I color the water in one of
these basins with a shade of dark purple brown, and the water in the other basin
with a shade of reddish brown, purple red, sea blue, a little laked carmine, a little
vermillion, and a very little of vegetable black. I then take a few silk threads,
cach about 16 to 20 inches long, and spread them on any surface, but I prefer a
sheet of zinc, the sides of which I turn up; then moisten this silk with a stock
I then take
soaked alternately in the two basins containing the coloured water.
off those threads from the surface where they were moistened by taking one of the
two ends in my two hands, and by having the other ends taken hold of by another
person's two hands; then thus aided by another person I lay those threads succes-
sively on the surface of operations, taking care beforehand to scatter all fibres,
so as to form games of veins and effects of marble, according to mineralogical and
geological order of real marble. After having thus laid out those moistened
threads on the surface of operation which are destined to form by their imprint the
veins of the first plan of the marble, and which threads are only to be taken from
the surface of operation when the background of the marble is formed, as pre-
viously described, I trace the veins of the second plan with the coloured cement or
plaster contained in the first six small basins with a silk thread used in the same way
as for making the veins of the white veined marble, but taking care to moisten this
thread in two or three of those shades, and sometimes in the whitish shades, before
making it touch the surface of operation, so as to vary the colour of the veins.
In short, I terminate the veining by forming the whitish veins and knots as they
are to be found in real sienna marble by the aid of a silk thread similar to the
one which was used for forming the veins above described moistened in the whitish
ninth part.
The veins thus traced, I take a certain quantity of one of the three
shades prepared for the background of the marble; I mix this coloured part with
the two or three shades prepared for the veins, then I sprinkle lightly this prepared
part on the veins formed on the surface of operation by throwing a little here and
there. I perform the same operations with the other two shades prepared for the
background of the marble, which I repeat until the veined part is entirely covered,
then finish as before described.
RED GRIOTTE.
The required quantity of cement or plaster being mixed, as before stated, I take
about an eighth part, which I divide into 5 equal parts in 5 basins. I colour the
first part with vegetable black; the second, with sea blue; the third, with vermillion;
the fourth, with laked carmine; and the fifth, destined to form the veins, and the
whitish knots as found in real marble must be slightly tinted with a little black, a
little blue, and a little red. I then divide the other seven-eighths, and the third about
an eighth; I then colour these three parts with red and light purple. The first part,
destined to form the greater part of the background of the marble, must be of a dark
bright red colour, the second darker than the first, and the third with rather a warmer
appearance than the two former parts. I darken these parts with the shades con-
tained in the first four basins; I then make two shades for the veins, which must
be of a dark brown colour, but one must be a little darker or lighter than the other.
I make these two shades for veins in two flat basins with a little of the first four
parts, and a little of those prepared for the background of the marble; these shades
for the veins must be less dense than those for the background. The shades for

page_text: the veins, as also those for the background of the marble, being thus prepared I
then trace the veins of the first plan with a square net about 20 inches long with
sides formed of silk fibres, or other suitable substance, of the size of a sewing
thread, and forming lozenges from an inch to of an inch a side, which said net
I moisten alternately in the two basins containing the shades of the veins by
holding it by the four corners aided by another person. This net thus moistened,
and still held by the four corners, I shake more or less, according to the veins to be
produced, whether large or small. I make it touch the surface of operation in order
that it may leave its imprint thereon, and I repeat the operation until the veins
appear sufficiently formed from the imprint of this net; then I touch up the outline
of veining with a single thread also moistened in the shades prepared for the
veins, and which I make touch the surface of operation as many times as I think
necessary with this same thread; I make also the white veins and knots by
moistening it in the shade prepared for that purpose. I then make the background
of the marble by passing separately through a sieve (on the veins traced on the
surface of operation) the shades prepared for that purpose, and finish as before
described, that is to say, in the same manner as for other marbles.
SEA GREEN.
I take about a fifth part of the cement or plaster, mixed in the manner before
stated, which I divide into four equal parts; I colour three of those four parts with
green, composed of china blue and light citron chrome, but I give to each of those threc
parts a different bearing, but in accordance with the shades of the veins of real
marble;
the fourth part, destined to form the whitish veins, must be slightly tinted
with green; the four parts above mentioned are for making the veins. I then
divide the other four-fifths of the remaining cement or plaster into three equal
parts; I colour these three parts destined to form the background of the marble
with vegetable black, but I make three distinct shades one from the other by adding
more or less of the green shades prepared for the veins. I make the shades of the
veins less dense than those of the background. The shades of the veins, as also
those of the background, being thus prepared, I commence to outline the veining
with silk threads which I hold by the ends, and aided by another person holding in
his hands the other ends, and I inoisten the said threads in the shades prepared for
the veins; then still holding this moistened thread in my hands, and aided by
another person, I make it touch the surface of operation so as to leave its imprint,
taking care beforehand to scatter the fibres so as to form games of veins and effects
of marble according to the geological and mineralogical order of the real marble.
I repeat this operation as many times as I think it necessary, that is to say, until
the outline is complete, after which I touch up this outline with a single thread
moistened in the shades prepared for the veins, and making it touch the surface of
operation in the same manner as to trace the veins of the white-veined marble
with the same thread; I trace veins and white knots here and there by
moistening this thread in the shade prepared for that purpose. The veining being
thus finished, I form the background of the marble by scattering lightly with the
hand on the veining the dark shades prepared for that purpose, but taking care
beforehand to mix them a little with the shades prepared for the veins, and finally
terminate the operation in the manner before described.
MARAMA.
A marble with dark red background and greenish brown, pebbled, veined with
pale green, a few yellowish and whitish veins, a few others rose colour, and a very
few bright green veins. To produce this marble, I commence by taking about an
eighth part of the mixed cement or plaster mixed as before stated, which I divido
into six equal parts; I then colour the first part with vegetable black, the second
with sea blue, the third with vermillion, the fourth with laked carmine, the fifth
with red chrome, and the sixth with green; these six parts just enumerated are

page_text: destined to shade the parts of the veins, as also the background of the marble. I
then take about another eighth part of the mixed cement or plaster to form the
veins, which I also divide into six parts of green; one of the last three parts must
be lightly tinted with green, another must be tinted with a little vermillion and a
little red chrome, so that it should have a rose reflex; the fourth part must be of
rather a bright red, composed of vermillion, a little laked carmine, a little red
chrome, and a little blue; the fifth part must have a rose tint, composed of
vermillion, a very little lake, a little red chrome, and a little green; the sixth part
destined to form the veins and the whitish knots must be slightly tinted with green
and vermillion. I then divide the other six-eighths of the cement or plaster in four
parts, as follows:-The first about 3/8, the second about 2/8, the third and fourth parts
about /, each. I then colour the first part with red, light purple, and I darken it
with a little black and a little blue, then I brighten it up with a little vermillion.
I give the second part a dark greenish brown tint, with red, purple, a little
black, green, and a little vermillion; the third part must be a little darker than the
second, but tinted with less green, and brightened up with a little lake; the fourth
part must be of bright red, composed principally of vermillion. These last four parts
are destined to form the background of the marble,
1
2
For this marble, the same as for nearly all others in general, the shades of the
veins must be less dense than those of the background. I form the veins of the
marama in a similar way to those of the sea green, but bearing in mind the
geological and mineralogical formation of real marble.
When the veining is formed on the surface of operation I scatter over the veining
through a sieve the parts prepared for the background, but each separately, com-
mencing with the brightest part, and then I terminate in the same manner as for
other marbles.
VIOLET BRECCIA.
I take about an eighth part of the mixed cement or plaster, according to the
formula before described, which I divide into six equal parts; I colour the first part
with laked carmine, the second with vermillion, the third with red purple, the
fourth with dark orange chrome, the fifth with blue, and the sixth with vegetable
black. I then take another eighth part of the mixed cement or plaster, which I
divide into seven equal parts, to make the shades for the veins; I give to the first
part, destined to form the principal veins, a dark brown shade, but brightened with
lake and a little vermillion, so that it should have a violet reflex to the third, a
bluish shade to the fourth, a yellowish shade, but brightened with vermillion, to the
fifth, also a yellowish shade, but lighter than the fourth, to the sixth a greenish
grey, and the seventh part must be as white as possible.
To make the shades of the notches I take first of all about another eighth part
of the aforesaid mixed cement or plaster, which I colour with lake, a little vermillion,
and a little blue and black; this part, destined to form the warmer appearance of
the marble, must be bright, and the lake must predominate. I then divide the
other five-eighths of the remaining cement into three equal parts; the first part
must be almost white, simply tinted with a little blue, a little vermillion, and a
little yellow; the second part must be tinted with lake, blue, and a little vermillion,
and must have a light violet reflex; the third part must be tinted with yellow. I
then form the veins on the surface of operation in the first instance with silk threads,
which I moisten in the shades prepared for the veins, but more especially in the
dark ones;
make these threads thus moistened touch the surface of operation by
the same means as described for the formation of the veins of sea green marble, then
with a single thread I form the veins of the notches by moistening this thread in
the shades prepared for that purpose, with the exception of the dark shade, which
only serves for the veins of the first plan, then with the last four shades I form the
notches, taking care to employ these shades separately, so as to form distinct
notches, nevertheless I mix them slightly, each separately; I run these shades for
forming the notches on the veined part with the hand or a kind of spoon.

page_text: to, I bear in mind the geological and mineralogical formation of real marble; in
short, I terminate the process for this marble in the same way as the others which
have preceded it.
PAVANA.
I make use of the same means to produce this marble as for violet breccia, but.
bearing in mind the effects of marble and the shades which characterize this marble.
The pavana is formed of almost regular whitish notchos, and sometimes shaded
with violet and yellow; the veins of the first plan are brown and dark grey, with a
bluish reflex.
SIRANCOLIN.
To produce this marble I take about an eighth part of the mixed cement or
plaster, according to the formula before described, which I divide into seven equal
parts, then proceed to colour the first part with purple red, the second with
vermillion, the third with lake, the fourth with red chrome, the fifth with a little
light citron chrome, the sixth with sea blue, and the seventh with vegetable black;
these seven parts just enumerated are only used for shading the parts of the veins and
those of the first plan of the marble. I then take another eighth part of the mixed
cement or plaster, which I divide into five parts to form the veins; the first of
those five parts being destined to form the predominant veins of the marble must
be of a dark bright red colour; I therefore tint this part with purple, red, vermillion,
a little lake, a little blue, and a little black; I tint the second part with the samo
colours, but rather darker than the first; I give the third part a yellowish and rose
tint, composed of a little lake, a little vermillion, and a little red chrome, this last
colour must however predominate; I give the fourth part a bluish tint, composed of a
little sea blue and a very little red chrome, a very little light citron chrome and a very
little vermillion. I then take another eighth part of the mixed cement or plaster,
which I divide into two equal parts; I give to one of these two parts a greyish blue
tint, and the other part I make as white as possible; those last two shades slightly
mixed are destined to form the little notches and the whitish grey veins of the
marble. Then I take another eighth part of the mixed cement or plaster, which I
tint slightly with light citron chrome, a little blue, and a little lake and vermillion;
this shade must be of a light yellowish colour very lightly expressed, and a little
green with a slight rose reflex. I then divide the remainder of the mixed cement or
plaster, that is to say, about one half of the whole quantity, into two equal parts; I
give to one of these two parts a greyish blue tint, and to the other a greyish red
tint, with a slight yellow reflex; these last three parts are destined to form the
background of the marble. The shades for the veins, as also those for the back-
ground of the marble, being thus all prepared, I take silk threads which I dip
alternately in the two parts prepared for forming the veins and the small whitish
grey notches; these threads thus dipped I bring into contact with the surface of
operation here and there, that is to say, I make them touch the surface of operation
as many times as I think necessary, and by the same means employed to form the
veins of the sea green before described, but with these last two shades I afterwards
form the small whitish grey notches. I then take other silk threads which I moisten
in the dark brown part prepared for the veins, and with these threads thus
moistened I form here and there veins, bearing in mind the geological and mineral-
ogical order of real marble; then with rather a thickish thread, which I dip
principally in the bright red tint, I form the trail of the bright red veins, but also
taking care to moisten this thread occasionally in the other parts prepared for the
veins, so as to alternate these shades, and to superpose them according to the
geological and nineralogical order of the real marble. I terminate the veining with
a thinner thread than the former, which I moisten in the light parts prepared for
the veins, and I make this thread thus moistened touch the surface of operation, so
as to form the veins of the second plan and the notches. When the veining is

page_text: times in one of the prepared parts for the background and sometimes in another of
thoso parts; with this thread thus moistened I form the third plan of the parts,
more or less notched with the shades prepared for that purpose, and terminate in
the same manner as for other marbles.
GREEN CAMPAN.
I take about a sixth part of the mixed cement or plaster; this part is destined
to form the thick transversal veins of the first plan of the marble; I tint it with a very
little green in order that that tint should appear white compared with the other
shades of the marble. I then divide the remainder of the cement into five equal
parts to form the background of the marble; I give to the first of those five parts a
pale greenish tint: to the second, likewise a pale greenish tint, but still lighter than
the first; to the third, a still paler green shade than the second; to the fourth, a rose
tint with a little lake, a little vermillion, and a little green; to the fifth, a dark red
tint composed of purple red, a little vermillion, and a very little lake, and a very
small quantity of black and green; I then take a small quantity of the first of
those five parts which I divide into two parts to make the shades for the veins; I
darken those two last parts with green and a little black in such a way that they
should clash with the parts of the background; one of those two veined parts must
have a slight greyish tint which I obtain by adding a little red.
When the shades of the background as also those for the veins are prepared, I
take rather a thick silk thread which I moisten in the whitish part so as to trace
the transversal veins by making it touch the surface of operation cach time it is
moistened; then with a net similar to the one described for the making of red
griotte, which I moisten alternately in the dark shades prepared for the veins, I
form the veins of the second plan by making this net touch the surface of operation
each time it is moistened, and in the same way as described for forming the veins
of the red griotte. Then I touch up that outline made with that net with a single
thread moistened in the same shades, and used in the same way as for forming the
veins of the white veined marble; I form the third plan of this marble by passing
successively through a sieve on the veins traced on the surface of operation the
shades prepared for that purpose by commencing by the first part which is the
darkest of the three, green shades prepared for the back ground. I only employ
the dark red shade at intervals, according to the bed of the real marble, and without
geological order. I finish this marble like the others which have preceded it, as
described in the general Specification.
TURQUOISE BLUE.
I take about a tenth part of the mixed cement or plaster, as before described,
which I divide into four equal parts. I color the first part with sea blue, the second
with vegetable black, the third part with a little vermillion, and the fourth with a
little lake. These four shaded parts are only used for coloring the back ground and
parts of the veins; then I take about seven-tenths of mixed cement or plaster
which I divide into three equal parts. I give to the first of those three parts a dark
blueish grey tint; to the second part also a blueish grey tint, but less blue and more
pale than the first; the third must be more pale than the two previous ones, and
must have a slight purple reflex which I obtain by adding a little vermillion, and a
little lake. These last three parts are destined to form the background of the
marble.
To make the shading of the veins I take in the first place another tenth part of
the remaining cement or plaster which I divide into two parts; I give to one of
these last parts a dark grey tint composed of blue and black; I give about the same
tint to the other part, but in order to give it a purple reflex I add a little lake and
o little voumillion as to the last or tenth part of mixed cement or plaster destined

page_text: to form the whitish parts of the marble I tint it slightly with blue and black, so that
this shade should appear white compared with the other shades of the marble. When
the shades for the veins as also those for the background of the marble are thus
prepared, I trace in the first instance the veins of the first plan with a single thread
rather thin moistened alternately in the two dark shades prepared for the veins.
These veins must nearly all be formed one way, that is to say, according to the bed
of the natural marble, and without geological or mineralogical order; I then form
the background by moistening a thicker silk thread than the former in the shades
prepared for the background, as also from time to time in the whitish shade, and
in inaking this thread thus moistened touch the surface of operation in the direction
of the veins, so that the rear plan appears to be formed of superposed coatings. I
form entirely that rear plan to that effect with the said thread, and then I terminate
the process in the saine manner as the preceding ones.
I employ the same means to form this marble as for the red griotte before
described, but I make the shades for the rear plan, as also the veins after the
natural colors relative to this marble.
PORTOR.
To produce this marble I take about an eighth part of the mixed cement or
plaster as previously explained, which I divide into four equal parts to make the
shades of the veins; I tint the first part with ordinary sienna earth, a little burned
sienna earth, a little red chrome, a little orange chrome, and a little vermillion. I
tint the second part with the same colors, but I make it paler than the first, the
third part must have a yellowish rose tint which I obtain by adding a little red
chrome, a little burned sienna earth, and a little lake and vermillion, the fourth
part destined to form the small veins and the small whitish notches as found in
real marble must be slightly tinted with black and blue. Then I divide the
remainder of the cement into two equal parts, which I color principally with
vegetable black, a little sea blue, and a little purple red. I make with these two
parts, destined to form the rear plan of the marble, two distinct tints. The shades
of the veins as also those of the background being thus made according to the
shades of the real marble, I take a rectangular shaped not about 20 inches long, and
ten inches wide, composed of silk fibres forming irregular lozenges, varying from
two-fifths of an inch to three inches about the side, which I moisten in the shades
prepared for the veins, and which I make touch the surface of operation here and
there, that is to say, according to the geological formation of the real marble, and
in the same manner as for forming the veins of red griotte; then with a single
thread I touch up that outline, and I form the whitish veins and notches; then if
the veining is too much charged I correct it by retouching the veins up with a
sponge and a small leather, the latter the same as used for polishing glass. The
veining thus formed I afterwards form the rear plan of the marblo by laying on on
that veining the shades prepared for that purpose, taking care beforehand to mix
them a little; then I terminate this marble in the same manner as the other
marbles.

page_text: in the levant red than in the marama; I notch the background here and there
with greenish red notches, and with blackish red notches with a greenish reflex:
To form the accentuated notches of the notched marbles, such for instance, as violet
breccia, sirancolin, levant red, and others, I form beforehand on a sheet of glass
independent of the surface of operation a veined coating according to the notches to
be produced with the shades prepared for the background, and the veins of the
marble that I wish to produce; then when this coating has been manipulated with
a trowel, and after having withdrawn the superfluous water as before indicated
with other marbles, and before it is set, I unfasten it from the glass in pieces, and
with care with a thin knife handled like a trowel, I slip the blade between the glass
and the veined coating, then I take off the parts of the veined coating thus un-
fastened with the said knife or a trowel of any kind, and I lay such parts suc-
cessively on the surface of operation, where after having pressed them down with a
trowel so that the veined side of thos parts should touch entirely the surface of
operation, and having pierced them here and there with a point so as to cause the
air bubbles to disappear, I then cut them out according to the shape of the notches
of the marble that is being imitated. To imitate stoned marble, such as brocatelle,
granite, porphyry, and other stones, I form the effects of those said marbles by
passing through a sieve the mixed and shaded cement or plaster, according to the
real marble that is to be imitated which I lay on the surface of operation. To
make a large size slab I make it on a surface of operation formed with a balanced
table on a horizontal axle in such a manner as to give to the said surface of
operation a vertical position; when the slab is to be taken off I make use of this
balanced surface of operation to prevent difficulties which would otherwise arise
from the taking off of the slab from an ordinary surface of operation, that is to say,
in a horizontal and immovable position. However when I havo no balanced surface
of operation at hand for making a large slab of any kind, I substitute an iron frame
which I fasten to the slab with cement, and by the aid of which I take off the said
slab from the surface of operations, or I employ any other suitable arrangement for
effecting the above object.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Emile de Laroque in the Great Seal Patent Office on the 4th September
1876.
EMILE DE LAROQUE, of 24, Leadenhall Street, in the City of London. " IMPROVE-
MENTS IN THE MANUFACTURE OF ARTIFICIAL MARBLES, GRANITES, AND OTHER 3
STONES."
The object of this Invention is more particularly to give to artificial marbles,
granites, and other stones during their manufacture the necessary colors to resemble
natural marbles and other stones either veined or otherwise marked.
The following is an example of the ingredients, matters, or substances I propose 4
to employ in and for the manufacture of marbles, granites, and other stones and
the manner of operating therewith.
PROCESS OF MANUFACTURE.
I propose to make artificial marbles either in panels, plane or curved mouldings,
columns, statues, and other objects of art and ornament. For this purpose I take 4
cement produced by combining gypsum with alum and mixed with pure water, or
plaster mixed with gum water. I then take colours (vegetable or mineral) ground
and mixed with water to shade the cement or plaster according to the kind of
marble to be imitated as hereafter described in classification. I also use canvas or
other like material to strengthen the article, and proceed as follows:-To produce 5
marble I commence by mixing with water in a suitable vessel the quantity of

page_text: cement or plaster required to make the veined surface of the object about to be
made. The cement or plaster thus mixed I divide in as many basins as may be.
required, according to the number of shades of the marble to be made as hereaftor
more fully indicated. Then on a surface that I call "surface of operations," plane
or curved on polished glass or other surface polished or non-polished, I trace in the
first instance the veins of the first plan of the marble with silk or other fibres
moistened with coloured water or coloured cement, according to the marble to be
made, which I will describe in the classification further on, then to form the founda-
tion or rather background of the marble I run the coloured cement or plaster
through the mould; or I place it by hand on the veins traced on the surface of
operations. I make these portions of different density, that is to say, I make the
parts destined to form the veins or the shades not so thickly mixed as those of
the background so as to produce varied shades and effects, according to the
mineralogical and geological order of the marble to be imitated. I make the veined
coating forming the background of the marble about one-tenth of an inch thick,
which I smooth down with a trowel; then if the veins have been made with
coloured moistened fibres I withdraw those fibres from the surface of operation
where they have by their imprint formed the veins of the marble; then smooth
down a second time the coating forming the background of the marble so as to fill
up the vacant space produced by the withdrawal of the fibres; then to prevent air
bubbles I stir for a short time the surface of operation, then withdraw the surplus
water; I was obliged to use to mix and colour the cement or plaster forming the
veined coating of the marble by sifting with a sifter a bed of cement or plaster in
powder on the aforesaid background coating, I then withdraw the powdered cement
or plaster a few minutes afterwards, that is to say, when it has absorbed the remainder
of the water which would prevent this veined coating from hardening; I then stir
the veined coating with a trowel to make it more compact and more adhering to
the lining used for strengthening the article that is to be made of which I shall
speak later on.
It is to be understood that the side of the coating which I stir with a trowel is
the opposite side to that which is in direct contact with the surface of operations
which is the veined side. To consolidate this slab moulding or any other article
whatsoever I back it with canvas or other similar material and then with another
coating of cement or plaster I fasten this canvas with cement or plaster mixed
slightly liquid so that it adheres to the coating forming the back of the marble; I
then spread on the aforesaid canvas thus fastened on this coating of the back of the
marble another coating of the marble of cement or plaster mixed of the required
thickness, according to the article that is being made (generally about two-fifths of
an inch thick). This last coating of cement or plaster being employed to consolidate
the article that is being made must be mixed with a very small quantity of water
so as to make a paste of it sufficiently compact which may be laid out with a trowel
or other similar utensil. When this slab moulding or other article made is
crystallized or hardened I take it from the surface of operation or from the mould
which it has been made upon and finish by filling up the pores of the veined surface
of this object; it is then polished with stones and other well known ingredients in
use for polishing marble.
When the slab moulding or other article made by the foregoing process is to be
used for decorating buildings I attach it to the walls or ceilings thereof by fixing
it with wire hooks which I fasten with cement or plaster, or with screws or
galvanized iron wedged in in wood (fastened to the walls or ceilings).
To make any article by the above process in an open or closed mould composed
of several pieces to form, for instance, a column, statue, or the like, I lay out before
hand all the parts of this mould on a table in such a manner that their ends
correspond, in order that when these parts are united the veins of the marble formed
on each part should be placed according to geological and mineralogical order of the
real marble imitated. On those parts of any mould thus laid out on a table I form
the veined coating the same as if it were on a surface of operation quite flat and

page_text: according to process described above, as also according to the marble to be produced,
as I shall speak of it in the classification of marbles to follow. When the veined
coating is formed and smoothed down, after having withdrawn the surplus water, I
put together the parts of the said mould; then the part of the mould left open I join
together with a spatula and finish by strengthening the moulded article as before-
described with canvas and cement or plaster.
To make articles with various inlaid marbles I make each veined part of these
marbles separately and successively on the surface of operation, that is to say, when
one part of the veined coating is formed on the surface of operation, and when
the surplus water has been withdrawn by the process described above, and smoothed
down, and whilst the cement is still moist I cut out that part with a knife, accord-
ing to the inlaying design, and I repeat the same operation separately for the other
parts of the different marbles until the design is entirely produced, and I finish the
inlaid article by strengthening it with canvas and cement or plaster, as before
described.
I now proceed to describe the classification of marbles and the means of pro-
ducing them, respectively, as follows :--
WHITE VEINED MARBLE.
To make this marble I commence, as previously described, by mixing in a suitable
vessel the requisite quantity of cement or plaster, according to the size of the article
intended to be made. I then take a sixteenth part of the mixed cement or plaster
and divide it into five equal parts in five basins. I then color the first of those five
parts with vegetable black, the second with sea blue, the third with yellow ochre,
the fourth with a very small quantity of vermillion, and the fifth with a small
quantity of light citron chrome. These five coloured parts above mentioned are
destined to shade the other parts for the background and the veins of the marble.
I then divide the remainder of the liquid cement or plaster into three parts, as
follows: The first part, the half of the remaining quantity of liquid cement; the
second, about the quarter; and the third, the remainder of the cement. The first of
these three quantities being required to predominate in the background of the
marble, I shade it lightly with the colouring contained in the first five basins; I
shade the second quantity more deeply than the first; and the third quantity, destined
to form the very white shade of the marble, if the cement or plaster is white
enough, I leave it its primitive colour, and then with a little of each of these last
three parts and a little of the first five I make three distinct shades for the veins.
It is to be understood that I make these shades according to mineralogical order
of the real marble. I make the shades of the background and outer plan of the marble
a little more dense than plaster when cast in a mould, and I make the shades of the
veins less dense than those of the background. I then take a silk thread, from 20 to
28 inches long, and according to the thickness required for the veins, and, holding
this thread by its ends dip it successively in the basins containing the shades pre-
pared for the veins; the thread thus dipped is made to touch the surface of opera-
tion in such a way that its imprint shall form a view, and I repeat this operation
until all the veins of the marble I desire to produce are traced on the surface of
operation. This being done, I take another thread of the same length, but much
thicker than the former one, which I dip in the basin containing the whitest shade,
and I make this thread touch the surface of operation in the same manner as for the
veins, in order to form by its imprint the parts traced lightly as they are to be
found in real white marble. When all the veins are thus traced I form the outer
plan of the marble in colour, or by spreading by hand on the surface of operation
when the veins are already formed the shades prepared for that purpose, taking care
to mix them a little in order to form plans and effects of different marbles; then, to
form the spotted parts, I spread by hand on the coating forming the background of
the marble through a sieve a little of each shade which has been used for making
the veins. I drop these shades with sufficient force to enable them to go through

page_text: the coating forming the background of the marble, and thus arrive at the first plan
and finish, as before described.
SIENNA.
To produce this marble I proceed in the following manner-The quantity of
cement or plaster, according to the article to be made, being mixed in the manner
before stated, I commence by dividing about the third of this mixed cement or
plaster into nine equal parts in nine basins; then I color the first part with light
citron chrome, the second with pale orange chrome, the third with dark orange
chrome, the fourth with red chrome, the fifth with laked carinine, the sixth with
vermillion, the seventh with tinted sea blue, the eighth with vegetable black, and
the ninth, destined to form the veins and white knots, must be tinted slightly with
blue, slightly with black, and slightly with light citron chrome. I then divide the
remainder of the mixed cement or plaster into three equal parts, and give them
three different shades, according to the marble, to be made light or dark with
ordinary sienna earth, a little burned sienna carth, and a little of each color con-
tained in the first six basins; then to form the veins of the first plan I take two
basins containing a sufficient quantity of water; I color the water in one of these
basins with a shade of dark purple brown, and the water in the other basin with a
shade of reddish brown, purple red, sea blue, a little laked carmine, a little ver-
million, and a very little of vegetable black. I then take a few silk threads, each
about 16 to 20 inches long, and spread them on any surface, but I prefer a sheet of
zinc, the sides of which I turn up, then moisten this silk with a stock soaked alter-
nately in the two basins containing the coloured water. I then take off these
threads from the surface where they were moistened by taking one of the two ends
in my two hands and by having the other ends taken hold of by another person's
two hands; then, thus aided by another person, I lay those threads successively on
the surface of operations, taking care beforehand to scatter all fibres so as to form
games of veins and effects of marble according to mineralogical and geological order
of real marble. After having thus laid out those moistened threads on the surface
of operation which are destined to form by their imprint the veins of the first plan
of the marble, and which threads are only to be taken from the surface of operation
when the background of the marble is formed as previously described, I trace the
veins of the second plan with the coloured cement or plaster contained in the first
six small basins with a silk thread used in the same way as for making the veins of
the white veined marble, but taking care to moisten this thread in two of those
shades, and sometimes in the whitish shades before making it touch the surface of
operation so as to vary the colour of the veins. In short I terminate the veining
by forming the whitish veins and knots as they are to be found in real sienna
marble by the aid of a silk thread, similar to the one which was used for forming
the veins above described moistened in the whitish ninth part. The veins thus
traced I take a certain quantity of one of the three shades prepared for the back-
ground of the marble. I mix this coloured part with the two or three shades
prepared for the veins; then I sprinkle lightly this prepared part on the veins formed
on the surface of operation by throwing a little here and there. I perform the
same operation with the other two shades prepared for the background of the
marble, which I repeat until the veined part is entirely covered, then finish as before
described.
RED GRIOTTE.
The required quantity of cement or plaster being mixed as before stated, I take
about an eighth part which I divide into 5 equal parts in 5 basins; I color the first

page_text: an eighth; I then colour these three parts with red and light purple; the first part
destined to form the greater part of the background of the marble, must be of a
dark bright red colour, the second darker than the first, and the third with rather a
warmer appearance than the two former parts. I darken these parts with the
shades contained in the first four basins; I then make two shades for the veins,
which must be of a dark brown color, but one must be a little darker or lighter
than the other; I make these two shades for veins in two flat basins, with a little of
the first four parts and a little of those prepared for the background of the marble.
These shades for the veins must be less dense than those for the background; the
shades for the veins as also those for the background of the marble being thus pre-
pared, I then trace the veins of the first plan with a square net about 20 inches
long, with sides formed of silk fibres or other suitable substance, of the size of a
sewing thread, and forming lozenges from an inch to of an inch a side, which
said net I moisten alternately in the two basins containing the shades of the veins.
by holding it by the four corners aided by another person; this net thus moistened
and still held by the four corners, I shape more or less, according to the veins to be
produced, whether large or small; I make it touch the surface of operation in order
that it may leave its imprint thereon, and I repeat the operation until the veins
appear sufficiently formed from the imprint of this net, then I touch up the outline
of veining with a single thread also moistened in the shades prepared for the veins,
and which I make touch the surface of operation as many times as I think necessary
with this same thread; I make also the white veins and knots by moistening it in
the shade prepared for that purpose; I then make the background of the marble
by passing separately through a sieve (on the veins traced on the surface of
operation) the shades prepared for that purpose, and finish as before described, that
is to say, in the same manner as for other marbles.
SEA GREEN.
I take about a fifth part of the cement or plaster mixed in the manner before
stated, which I divide into four equal parts; I colour three of those four parts with
green, composed of China blue and light citron chrome, but I give to each of those
three parts a different bearing, but in accordance with the shades of the veins of
real marble; the fourth part destined to form the whitish veins must be slightly
tinted with green; the four parts above mentioned are for making the veins. I
then divide the other four-fifths of the remaining cement or plaster into three equal
parts; I colour these three parts destined to form the background of the marble with
vegetable black; but I make three distinct shades one from the other, by adding
more or less of the green shades prepared for the veins; I make the shades of the
veins less dense than those of the background. The shades of the veins as also those
of the background being thus prepared I commence to outline the veining with silk
threads, which I hold by the ends, and aided by another person holding in his hands
the other ends, and I moisten the said threads in the shades prepared for the veins,
then still holding this moistened thread in my hands, and aided by another person
I make it touch the surface of operation, so as to leave its imprint, taking care
beforehand to scatter the fibres so as to form games of veins, and effects of marble,
according to the geological and mineralogical order of the real marble. I repeat this
operation as many times as I think it necessary, that is to say, until the outline is
complete, after which I touch up this outline with a single thread moistened in the
shades prepared for the veins, and making it touch the surface of operation in the
same manner, as to trace the veins of the white veined marble; with the same thread
I trace veins and white knots here and there by moistening this thread in the shade
prepared for that purpose. The veining being thus finished I form the background
of the marble by scattering lightly with the hand on the veining the dark shades
prepared for that purpose, but taking care beforehand to mix them a little with the
shades prepared for the veins, and finally terminate the operation in the manner
before described.

page_text: MARAMA.
A marble with dark red background and greenish brown, pebbled, veined with
pale green, a few yellowish and whitish veins, a few others rose colour, and a very
few bright green veins. To produce this marble I commence by taking about an
eighth part of the mixed cement or plaster mixed as before stated, which I divide
into six equal parts; I then colour the first part with vegetable black, the second
with sea blue, the third with vermillion, the fourth with laked carmine, the fifth
with red chrome, and the sixth with green. These six parts just enumerated aro
destined to shade the parts of the veins, as also the background of the marble; I
then take about another eighth part of the mixed cement or plaster to form the
veins, which I also divide into six parts of green; one of the last three parts must
be lightly tinted with green; another must be tinted with a little vermillion and a
little red chrome, so that it should have a rose replex; the fourth part must be of
rather a bright red composed of vermillion, a little laked carmine, a little red
chrome, and a little blue; the fifth part must have a rose tint composed of
vermillion, a very little lake, a little red chrome, and a little green; the sixth part
destined to form the veins, and the whitish knots must be slightly tinted with
green and vermillion; I then divide the other six-eighths of the cement or plaster
in four parts as follows:-The first about 2/, the second about 2/, the third and
fourth parts about 1/8 each; I then colour the first part with red light purple, and
I darken it with a little black and a little blue; then I brighten it up with a little
vermillion. I give the second part a dark greenish brown tint with red purple, a
little black green and a little vermillion; the third part must be a little darker
than the second, but tinted with less green, and brightened up with a little lake;
the fourth part must be of bright red, composed principally of vermillion. These
last four parts are destined to form the background of the marble.
For this marble, the same as for nearly all others, in general the shades of tho
veins must be less dense than those of the background. I form the veins of the
marama in a similar way to those of the sea green, but bearing in mind the
geological and mineralogical formation of real marble.
When the veining is formed on the surface of operation scatter over the veining
through a sieve the parts prepared for the background, but cach separately,
commencing with the brightest part, and then I terminate in the same manner as
for other marbles.
VIOLET BRECCIA.
I take about an eighth part of the mixed cement or plaster, according to the
formula before described, which I divide into six equal parts; I colour the first
part with laked carmine, the second with vermillion, the third with red purple, the
fourth with dark orange chrome, the fifth with blue, and the sixth with vegetable
black; I then take another eighth part of the mixed cement or plaster, which I
divide into seven equal parts, to make the shades for the veins; I give to the first
part destined to form the principal veins a dark brown shade, but brightened with
Iako and a little vermillion, so that it should have a violet reflex; to the third a
blueish shade; to the fourth a yellowish shade, but brightened with vermillion; to
the fifth also a yellowish shade, but lighter than the fourth; to the sixth a greenish
grey; and the seventh part must be as white as possible.
To make the shades of the notches I take first of all about another eighth part
of the aforesaid mixed cement or plaster, which I colour with lake, a little
vermillion, and a little blue and black. This part, destined to form the warmer
appearance of the marble, must be bright, and the lake must predominate; I then
divide the other five-eighths of the remaining cement into three equal parts; the
first part must be almost white, simply tinted with a little blue, a little vermillion,
and a little yellow; the second part must be tinted with lake, blue, and a little
vermillion, and must have a light violet reflex; the third part must be tinted with
yellow; I then form the veins on the surface of operation in the first instance with

page_text: take other silk threads, which I moisten in the dark brown part prepared for the
veins, and with these threads thus moistened I form here and there veins, bearing
in mind the geological and mineralogical order of real marble; then with rather a
thickish thread, which I dip principally in the bright red tint, I form the trail of
the bright red veins, but also taking care to moisten this thred occasionally in
the other parts prepared for the veins, so as to alternate these shades and to
superpose them, according to the geological and mineralogical order of the real
marble. I terminate the veining with a thinner thread than the former, which I
moisten in the light parts prepared for the veins, and I make this thread thus
moistened touch the surface of operation, so as to form the veins of the second plan
and the notches. When the veining is finished I take a thread twice as thick as
that first mentioned, moistening it sometimes in one of the prepared parts for the
background, and sometimes in another of those parts with this thread thus
moistened. I form the third plan of the parts more or less notched with the
shades prepared for that purpose, and terminate in the same manner as for other
marbles.
GREEN CAMPAN.
I take about a sixth part of the mixed cement or plaster. This part is destined
to form the thick transversal veins of the first plan of the marble. I tint it with a
very little green in order that that tint should appear white compared with the
other shades of the marble. I then divide the remainder of the cement into five
equal parts to form the background of the marble. I give to the first of those five
parts a pale greenish tint; to the second likewise a pale greenish tint, but still
lighter than the first; to the third a still paler green shade than the second; to the
fourth a rose tint, with a little lake, a little verinillion, and a little green; to the
fifth a dark red tint composed of purple, red, a little vermillion, and a very little
lake, and a very small quantity of black and green. I then take a small quantity
of the first of those five parts, which I divide into two parts to make the shades for
the veins. I darken those two last parts with green and a little black in such a
way that they should clash with the parts of the background. One of those two
veined parts must have a slight greyish tint, which I obtain by adding a little red.
When the shades for the background as also those for the veins are prepared I
take rather a thick silk thread, which I moisten in the whitish part so as to trace
the transversal veins by making it touch the surface of operation each time it is-
moistened, then with a net similar to the one described for the making of red
griotte, which I moisten alternately in the dark shades prepared for the veins. I
form the veins of the second plan by making this net touch the surface of
operation each time it is moistened, and in the same way as described for forming
the veius of the red griotte; then I touch up that outline made with that net with a
single thread moistened in the same shades and used in the same way as for forming
the veins of the white veined marble. I form the third plan of this marble by
passing successively through a sieve on the veins traced on the surface of operation
the shades prepared for that purpose by commencing by the first part, which is the
darkest of the three green shades prepared for the background. I only employ the
dark red shade at intervals, according to the bed of the real marble, and without
geological order. I finish this marble like the others which have preceded it as
described.
TURQUOISE BLUE.
I take about a tenth part of the mixed cement or plaster, as before described,
which I divide into four equal parts. I colour the first part with sea blue, the
second with vegetable black, the third part with a little vermillion, and the fourthi
part with a little lake. These four shaded parts are only used for colouring the back-
ground and parts of the veins. Then I take about seven-tenths of mixed cement or
plaster, which I divide into three equal parts. I give to the first of those three
parts a dark blueish grey tint, to the second part also a blueish grey tint, but less
B

page_text: blue and more pale than the first; the third must be more pale than the two
previous ones, and must have a slight purple reflex, which I obtain by adding a
little vermillion and a little lake. These last three parts are destined to form the
background of the marbles.
To make the shading of the veins I take in the first place another tenth part of
the remaining cement or plaster, which I divide into two parts. I give to one of
these last parts a dark grey tint composed of blue and black; I give about the
same tint to the other part, but in order to give it a purple reflex I add a little lake
and vermillion. As to the last or tenth part of mixed cement or plaster destined to
form the whitish parts of the marble I tint it slightly with blue and black, so that
this shade should appear white compared with the other shades of the marble.
When the shades for the veins as also those for the background of the marble are thus
prepared I trace in the first instance the veins of the first plan with a single thread
rather thin, moistened alternately in the two dark shades prepared for the veins.
These veins must nearly all be formed one way, that is to say, according to the.
bed of the natural marble, and without geological or mineralogical order. I then
form the background by moistening a thicker silk thread than the former in the
shades prepared for the background, as also from time to time in the whitish shade,
and in making this thread thus moistened touch the surface of operation in the
direction of the veins, so that the rear plan appears to be formed of superposed
coatings. I form entirely that rear plan to that effect with the said thread, and
then I terminate the process in the same manner as the preceding ones.
employ the same means to form this marble as for the rod griotte before
described, but I make the shades for the rear plan, as also the veins, after the
natural colours relative to this marble.
PORTOR.
To produce this marble I take about an eighth part of the mixed cement or
plaster, as previously_explained, which I divido into four equal parts to make the
shades of the veins. I tint the first part with ordinary sienna earth, a little burnt
sienna earth, with a little red chrome, a little orange chrome, and a little vermillion;
I tint the second part with the same colours, but I make it paler than the first; the
third part must have a yellowish rose tint, which I obtain by adding a little red
chrome, a little burned sienna earth, and a little lake, and vermillion; the fourth
part, destined to form the small veins and the small whitish notches as found in
real marble, must be slightly tinted with black and blue. Then I divide the
remainder of the cement into two equal parts, which I colour principally with
vegetable black, a little sea blue, and a little purple red. I make with these two
parts destined to form the rear plan of the marble two distinct tints. The shades
of the veins, as also those of the background, being thus made according to the
shades of the real marble, I take a rectangular shaped net about 20 inches long and
10 inches wide, composed of silk fibres forming irregular lozenges varying from
2/ths of an inch to 3 inches about the side, which I moisten in the shades prepared
for the veins, and which I make touch the surface of operation here and there, that is
to say, according to the geological formation of the real marble, and in the same
manner as for forming the veins of red griotte; then with a single thread I touch
up that outline, and I form the whitish veins and notches; then if the veining is
too much charged I correct it by retouching the veins up with a sponge and a small

page_text: leather, the latter the same as used for polishing glass. The veining thus formed I
afterwards form the roar plan of the marble by laying on on that veining the shades
prepared for that purposo, taking care beforehand to mix them a little; then I
terminate this marble in the same manner as the other marbles.
LEVANT RED.
I produce this marble by very much the same means as for the marama marble
previously described, the shades differing only slightly, but I make less green veins
in the levant red than in the marama. I notch the background here and there
with greenish red notches, and with blackish red notches with a greenish reflex. To
form the accentuated notches of the notched marbles, such, for instance, as violet,
breccia, sirancolin, levant red, and others, I form beforehand on a sheet of glass
independent of the surface of operation a veined coating, according to the notches to
be produced with the shades prepared for the background, and the veins of the
marble that I wish to produce; then when this coating has been manipulated with
a trowel, and after having withdrawn the superfluous water as before indicated
with other marbles, and before it is set, I unfasten it from the glass in pieces, and
with care with a thin knife handled like a trowel I slip the blade between the
glass and the veined coating; then I take off the parts of the veined coating thus
unfastened with the said knife or a trowel of any kind, and I lay such parts
successively on the surface of operation, where after having pressed them down
with a trowel, so that the veined side of those parts should touch entirely the
surface of operation, and having pierced them here and there with a point so as to
cause the air bubbles to disappear; I then cut them out according to the shape
of the notches of the marble that is being imitated. To imitate stoned marble, such
as brocatelle granite, porphyry, and other stones I form the effects of those said
marbles by passing through a sieve the mixed and shaded cement or plaster,
according to the real marble that is to be imitated, which I lay on the surface of
operation. To make a large sized slab I make it on a surface of operation formed
with a balanced table on an horizontal axle, in such a manner as to give to the said
surface of operation a vertical position when the slab is to be taken off. I make
use of this balanced surface of operation to prevent difficulties which would other-
wise arise from the taking off of the slab from an ordinary surface of operation,
that is to say, in a horizontal and immovable position. However, when I have no
balanced surface of operation at hand for making a large slab of any kind I
substitute an iron frame, which I fasten to the slab with cement, and by the aid of
which I take off the said slab from the surface of operations; or I employ any other
suitable arrangement for effecting the above object.
VIOLET VEIN.
To produce this marble I proceed in the following manner: The quantity of
cement or plaster, according to the article to be made, being mixed in the same way
as indicated in the general Specification, I commence by mixing a sufficient quantity
of purple brown and raw umber for veining purposes; I then lay on the silk threads
or other fibres, having previously been moistened in the above colours; I then
divide the cement or plaster into three parts. The first part I colour with deep
Persian red, from which I make two shades, light and dark, the second with purplo
brown, and the third slightly tinted with Prussian blue; I then proceed in every
respect the same as for making sienna marble previously described.
ST. ANN.
To make this marble I commence as described in the general Specification by
mixing in a suitable utensil the requisite quantity of cement or plaster, according to
the size of the article to be made; I then take a tenth part of the mixed cement or
plaster, which I tint with the smallest possible quantity of black, so as to form a
greyish shade; the remainder of the mixed cement or plaster I colour with vegetable

page_text: black, which I pass through a sieve on to the surface of operations. The first of
these parts is then thrown violently on to the other, by which means it arrives at
the first plan of the marble; I then terminate this marble as indicated in the
general Specification.
BARDILLA.
A marble with grey background profusely striped with thick black veins. The
formula described at the commencement of each inarble having been complied with
I take two-thirds of the mixed cement or plaster, which I shade with a small
quantity of black, which produces the grey tint required, which is then laid on the
surface of operations in the usual manner; I then take the remaining third of the
mixed cement. or plaster, which I shade heavily with black, and lay it on the
surface of operations with a thick thread having a few scattered fibres here and
there; I then terminate the operation in the manner before described.
ROUGE.
This marble having a red background and whitish veins and notches is produced
in the following manner:-The requisite quantity of cement or plaster having been
mixed in a proper utensil, as previously described, I then take rather more than
two-thirds of the mixed cement or plaster, which I colour with Indian red, a little
raw sienna, and Persian red. The remainder of the aforesaid mixed cement or
plaster I tint slightly with ultramarine blue; I then take a silk thread of the usual
size, which I dip in the aforesaid shade and trace the veins on the surface of
operations. The notches are made with a much thicker thread, having here and
there a quantity of fibres attached together; I then lay on the first part in the
usual manner, and terminate as previously described.
Having now described the nature of my said Invention for "Improvements in the
Manufacture of Artificial Marbles, Granites, and other Stones," I would remark in
conclusion that I hereby declare my Invention to consist in, and I claim manu-
facturing artificial marbles, granites, and other stones, substantially as herein-before
described.
In witness whereof, I, the said Emile de Laroque, have hereunto set our hand
and seal, this Second day of September, in the year of our Lord One
thousand eight hundred and seventy-six.
EMILE DE LAROQUE.
(L.S.