The Manufacture of Variegated or Veined Artificial Stone and Imitations of Natural Marble.
Year: 1892

page_text: COMPLETE SPECIFICATION.
The Manufacture of Variegated or Veined Artificial Stone and
Imitations of Natural Marble.
I, PIERRE AIGNAU MOREAU, of Meung-sur-Loire (Loiret) in the Republic of
France, Marble Workman, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
:
This invention relates to the manufacture of variegated or veined artificial stone
and imitations of natural marble, by the use of coloured compositions which are
intermingled so as to imitate as nearly as may be the desired colours and veining of
natural stones. The articles may be either in the form of blocks to be afterwards
worked or in the finished or partly finished form which is desired.
According to my invention I use any suitable cement, plaster or other composition
which is capable, like plaster of Paris or Portland cement, of heing mixed into a..
semi-liquid or pasty form and poured into or otherwise placed in a mould and after-
wards of setting sufficiently hard for the purpose for which it may be required, or
of setting sufficiently to be afterwards submitted to a hardening process.
I prepare as many different portions of such composition as may be required, and...
I colour each of such portions with any suitable colouring material, so as to have a
series of portions of composition coloured for each shade of colour which it is pro-
posed to use. I then pour or otherwise place in a mould or suitable receptacle such
compositions, causing them to intermingle in such a manner as to produce varie-
gated veins, streaks or layers of the diversely coloured portions of composition.
The operator may conduct the intermingling in such a way as to imitate as far as
may be the streaks and veins of natural stone. The mass of variegated composition
thus produced must be allowed to set and a block or other article is thus produced
veined in different colours, not merely on the surface, but throughout the interior.
thereof. Hence it follows that such block or article may be cut, scraped, washed
or finished in such a way as altogether to remove the superficial layer, without
losing the veining or variegation, which goes throughout. The block or other
article may in most cases be afterwards hardened by immersion in a bath of sulphate
of zinc as hereinafter described, or in any other suitable manner.
A composition which I have found to be of great utility for the purposes of my
invention is formed by taking porous stone such as chalk, Portland stone or Bath
stone, reducing it to a fine powder passing it through a fine sieve, thoroughly drying
the powder and mixing it into a paste with water, sulphate of zinc and the requisite
colouring matters. Such a composition after it has set may be further hardened so
as to transform it into a very hard stone which will take a polish and serve as an
imitation of natural marble.
I will describe my invention more in detail as carried out with the use of such a
composition made from powdered chalk, in order to imitate as far as may be a red
marble of the kind known as St. Augustin.
After the chalk has been reduced to a fine powder and passed through a fine
sieve and after thoroughly drying the powder I prepare therefrom the following
compositions in about the proportions stated, namely:-
A. 1 kilogram of the powdered stone and 20 grammes of sesquioxide of iron.
B. 1 kilogram of the powdered stone, 20 grammes of sesquioxide of iron and
3 grammes of indigo blue.
C. 1 kilogram of the powdered stone, 40 grammes of sesquioxide of iron and
7 grammes of indigo blue; and,
D. 1 kilogram of the powdered stone, 80 grammes of sesquioxide of iron and
15 grammes of indigo blue.
I take a sufficient quantity of each of the four above named mixtures and form
21

page_text: them separately into a paste by the addition of a solution of one part of sulphate
of zinc of a strength of about 33 degrees Beaumé and two parts of water. I then
separately pour into a vessel a quantity of each of these four different mixtures,
one after the other but do not mix them, so that I obtain' a pasty mass variously
coloured, that is to say, which has not the same shade of colour throughout.
5%
I now pour this variegated composition or compound' of differently shaded
mixtures into a mould (previously greased) allowing it to pass out of the vessel
through a spout or the like in a thin stream depositing it in the mould in an irregular
or zig-zag way in such a manner as to form streaks, veins or the like to, as far as
possible, represent the veining of the marble to be imitated, or I may take four
different vessels one for each colour and intermingle the streams in different
proportions by pouring the coloured compositions into the mould.
The material is then, left to dry when it assumes a hardness about equal to
ordinary plaster and this I find usually takes place in about 48 hours. Or the
material may be left for about 24 hours, the further hardening and drying being.
then effected by the application of artificial heat.
The moulded article having been thoroughly dried may then be hardened by
being steeped in a bath of sulphate of zinc and treated according to the hardening
process described in the Specification of my former application No. 50 of 1892; it
is then ready to be finished and polished in the usual manner.
In some cases instead of employing the materials in the form of paste which can
be poured out of a vessel as hereinbefore described I sometimes employ the mixtures
in the form of a thick paste or dough and work them up together by means of a.
trowel or the like so as to produce the required clouding or veining and then mould
the material and treat it in the manner hereinbefore described.
Where required I can cover with my improved compound, blocks or pieces of
chalk, stone, slate, glass or cement and after being submitted to the hardening
process it will be found that the scone or other core will be hardened as well as the
coating. Or the pieces of chalk, stone, slate or glass may be faced with my
compound. In practice I find it is advantageous to previously moisten with water
the stone or other material to be covered or faced.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed; I declare that what I
claim is:
1. The manufacture of variegated or veined artificial stone by the preparation of
diversely coloured compositions of a semi-liquid or pasty consistency and the inter-
mingling of such compositions in the semi-liquid or pasty state, so as to produce the
required variegation of colour and afterwards allowing such compositions to set,
substantially as described.
2. The manufacture of variegated or veined artificial stones and imitations of
natural marbles, by the preparation and intermingling of diversely coloured com-
positions made of powdered chalk or Portland or Bath stone or similar porous
stones nixed with water, sulphate of zinc and suitable colouring matters, substan-
tially as described, the variegated compositions being afterwards allowed to set and
subsequently harden by immersion in a bath of sulphate of zinc or in any other
suitable manner, substantially as described.
3. Moulded articles of variegated colours made substantially as hereinbefore
described.
4. The use of a composition of powdered chalk or other suitable stone mixed
with sulphate of zinc and water, substantially as and for the purposes hereinbefore
described.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.