Improvements in the Manufacture of Artificial Stone.
Year: 1889

page_text: Date of Application, 18th Feb., 1889
Specification Accepted, 25th May, 1889
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Artificial Stone.
We, ARCHIBALD CAMPBELL PONTON, of Viewfield, Parkstone, in the County of
Dorset, Architect, BENJAMIN LEWIN MOSELY, of 36 Robertson Street, Hastings, in the
County of Sussex, Surgeon Dentist, and CROMPTON CHAMBERS, of Town Hall
Chambers, Hastings, in the County of Sussex, Solicitor, 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:―
This invention relates to the manufacture of an artificial stone in which we usually
employ, sand, (with or without other material), and a carbonate of lime, such as
whiting. These materials are mixed with a siliceous hydrogel dissolved in an alkaline
silicate, which is used as a binding cement, to form a plastic mass. The mass is then
moulded as required, and the moulded articles are subsequently heated in an oven
until the cement has crystallized, when they are removed. It is to be noted that we
may employ the cement and whiting only. when we require a very fine grained
material, or mix sand therewith in any desirable proportion.
We reduce the carbonate of lime to an impalpable powder, sometimes mixing with
it sand or other siliceous, or earthy matter, in a granular or powdered state.
We then
make a siliceous cement, for binding the above named powdered or granular matter,
by the admixture of one part by volume of silicate of soda or potash (or combination
thercof), to two or three parts by volume of freshly prepared silicic acid in its
hydrogel state, and the latter is dissolved in the former. We then mix a sufficient
quantity of this liquid siliceous cement with the powdered or granular materials afore-
said, to make the whole into a plastic mass. The mass is then moulded as required,
and the moulded articles are afterwards placed in an oven, heated to a temperature of,
or about 360 degrees Fahrenheit, until it is thoroughly dried. The moulded articles
may subsequently be further treated by prolonged soaking in a bath of the above
described hot siliceous fluid or cement until the carbonate of lime has been changed
into chert, when they are removed and dried.
We also make an artificial calcareous sandstone by taking one part of whiting and
two or three parts of sand, and mix these together with the before mentioned liquid
cement to form a plastic mass. After the compound has been moulded into the shapes
1 Price 11

page_text: required, and dried in the oven, the product may be further treated by immersion in
a hot silica bath, with or without pressure, until the carbonate of lime has been changed
into chert, as already mentioned.
It is to be noted that the term hydrogel, as used herein, is applied to silica in a
gelatinous condition, and merely means a more insoluble state than the hydrosol. The
hydrogel is prepared by neutralizing the alkali, in a weak solution of silicate of soda,
with hydrochloric acid; thus forming common salt in the water and silica. The salt
As much water as
is washed away, and silica left in its hydrogel or gelatinous state.
possible, is squeezed out, and this hydrate of silica is dissolved in a solution of silicate
of soda until the bulk of the latter becomes two or three times greater.
Chert is formed by the contact of this hydrate of silica with carbonate of lime or
whiting. Heat, length of time, and pressure aid the chemical combination.
Having now particularly described and ascertained the nature of our said Inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is:
1. A liquid siliceous cement composed of a siliceous hydrogel and an alkaline silicate
made in the manner and in the proportions herein named, for binding together
pulverilent, granular or coarse material; substantially as described.
2. The combination of the lierein described siliceous binding cement with a carbonate
of lime for the purpose of manufacturing artificial stone; substantially as described.
3. In the manufacture of artificial stone, the combination of the herein described
siliceous binding cement with powdered whiting and sand; substantially as
described. 1
4. In the manufacture of artificial stone, the combination of the herein described
siliceous binding cement with sand or other material and a carbonate of lime to form a
plastic mass, and the exposure of moulded articles of the said mass to a heat of or
about, 360 degrees Fahrenheit; substantially as and for the purpose described.
5. The manufacture of artificial silicified limestone, or calcareous sandstone;
substantially as described.
FAIRFAX & WETTER,
433, Strand, London,
Agents for the Applicants.