An Improved Process for the Manufacture of Artificial Stone and Marble.
Year: 1891

page_text: Date of Application, 12th Sept, 1891
Complete Specification Left, 9th June, 1892-Accepted, 9th July, 1892
PROVISIONAL SPECIFICATION.
An Improved Process for the Manufacture of Artificial Stone
and Marble.
I, GUSTAV DOLENZ of Münzengrabenstr., Graz, in the Empire of Austria,
Engineer, do hereby declare the nature of this invention to be as follows:-
In carrying out this invention I employ for the production of plain or uncoloured
artificial stone or marble, from 1 to 5 parts finely ground burnt magnesite ;
2 to 3 parts clean washed crystal sand and 4 to 5 parts 34% chloride of magnesium-
lye. These ingredients are intimately mixed together to form a pasty mass which
may either be spread out to the desired thickness on a glass table or poured whilst
stirred into a suitable mould previously washed with chloride of magnesium-lye. It
is then placed in a chamber to be dried by exposure to a constant temperature
of 80° R. during about 20 hours.
When it is desired to produce veined stone or marble I make a mixture similar
to that above described which I colour with an earth colour corresponding to the
kind of stone or marble to be imitated. I add this coloured mixture to that first
described and stir the two together preferably by means of a round wood bar.
In order to obtain a beautiful veiny appearance the uncoloured mixture is made
thinner than the coloured mixture. In this way the latter is distributed in a
thread
like or vein form in the thinner substance. The coloured composition so produced
is then treated in the manner described for the uncoloured stone or marble.
Dated this 12th day of September 1891.
CAPITAINE & VON HERTLING,
89, Chancery Lane, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Process for the Manufacture of Artificial Stone
and Marble.
I, GUSTAV DOLENZ of Münzengrabenstr., Graz, in the Empire of Austria,
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
In carrying out this invention I employ for the production of artificial stone a
mixture of burnt magnesite, clean sand, and chloride of magnesium lye, which
mixture is poured into suitably shaped moulds. These latter may be of wood or
metal and constructed-in-one or more parts. Inside they are smooth coated with
lacquer, varnish, or other suitable substance. The more finished the artificial stone
is to be the more carefully must the coating be applied to the mould and when it is
intended to give the artificial stone the smooth polished appearance of polished
natural stone the mould must be hot lacquered. The more even and smooth the
surface of the mould, the more regularly smooth is the surface of the moulded
object after hardening. If, for instance, it is desired to produce a roof tile I mix
together 1 part magnesite powder, 4 to 5 parts sand and 2 parts chloride of
magnesium-lye of from 23° to 28° Beaumé. I use for this purpose a mould of
ordinary wood of the corresponding shape, lacquered or coated. After washing out
the mould with chloride of magnesium lye and greasing it with ordinary oil I pour
said mixture into it and leave it to dry during about 24 hours at the ordinary
temperature. At the end of this time the tile is ready for use.
For the production of stone like bricks of fine quality with a brilliant glazed

page_text: surface I use a mixture composed of 1 part magnesite powder, 2 to 4 parts clean
sharp sand and 14 to 14 parts chloride of magnesium lye of from 26° to 35° Beaumé.
In this case the moulds are of hard wood or plate metal (the latter being preferred)
and hot lacquered. They are afterwards carefully washed and greased with oil,
the mixture then poured in and dried as before stated. After drying the objects
are taken from the moulds and washed several times when they present a beautiful
bright surface.
For the production of artificial marble I use a mixture composed of 4 to 5 parts
finely ground burnt magnesite, 2 to 3 parts crystal sand and 4 to 5 parts chloride
of magnesium lye of from 23° to 35° Beaumé, more highly concentrated lye being
used for the more superior qualities of the artificial goods. To obtain with this
mixture, objects having the appearance of being highly polished, only metal moulds
which have been hot lacquered, carefully cleaned and oiled, are used. For fine
goods of this description the oil used should be a pure mineral oil. The pouring
and drying operations are similar to those before stated. After drying, the objects
are taken from the moulds and well washed several times when they present a
beautiful bright surface.
When it is desired to produce veined or streaked artificial stone or marble, two
like mixtures are made, the one coloured with the corresponding earth colour and
then stirred in with the other-the white mixture. Very beautiful veins or streaks
may also be produced by painting or colouring the design on the inside of the
mould with the coloured mixture and then pouring the white mixture into the
mould. When the mixture is being poured it is advisable to shake the mould.
Upon withdrawal from the moulds the objects are left to dry by exposure to the
air for about four days.
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 production of artificial stone or marble composed of powdered magnesite,
sand, and chloride of magnesium solution or lye, which mixture is poured into
moulds and dried substantially as described and shewn.
2. In the production of artificial stone or marble the use of moulds lacquered or
coated over, washed with chloride of magnesium solution and greased with oil
substantially as described.
3. The several processes for the production of polished or unpolished artificial
stone or marble substantially as described.
Dated this 9th day of June 1892.
CAPITAINE & VON HERTLING,
89, Chancery Lane, London, W.C., Agents for the Applicant.