Improvements in Plaster, Cement and the like.
Year: 1899

page_text: Date of Application, 14th Nov., 1899-Accepted, 30th Dec., 1899
COMPLETE SPECIFICATION.
Improvements in Plaster, Cement and the like.
I, CARL STRAUB, of the Town of Otisco, in the County of Onondaga, State of
New York, United States of America, Chemist, 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:-
My composition consists of the following ingredients, combined substantially
in the proportions stated, viz.:
Slaked lime (pure or impure) 1 cubic foot.
Aluminum oxide, or bauxite, from 1 foot to 4 cubic feet..
Water substantially pure in quantity sufficient to form a plastic or semi-liquid
mass, as desired. These ingredients are to be thoroughly mingled by agitation.
A quantity of fine mica may be included in the proportion of aluminum oxide to
render the composition more heat resisting. My composition produces a com-.
paratively inexpensive and durable cement or plaster for building purposes.
By aluminum oxide I mean hydrated aluminum oxide which is found in
considerable quantities in some of the States of the Union, more particularly
Georgia, Alabama and Florida, which are known to have considerable deposits.
of aluminum oxide, commonly called bauxite, and in Virginia, North and South
Carolina, where the primary rock is found in various states of transition from the
state of intact crystallization to perfect decomposition. In most instances, it forms
part of extensive rock formations, either of primary origin, or as the producț
of subsequent transition.
Granite, geneiss, syenite, schistose rocks, in state of deterioration, forming
immense beds of this crumbling and soft material, soft rocks of later formation,
especially argillaceous shales, as the Hamilton and Marcellus shales and the
stones of the Salina formation in New York State are well adapted for use in
the manufacture of my cement when combined with slacked lime.
The main sources for obtaining alumina (oxide of aluminum) in suitable
quantities are mainly those coming from decayed primary rock which is in a
state of decomposition, so far advanced, as to form a powdery substance, casily
ground between the fingers, but not so far advanced, as to form true clay. In
this state it forms immense deposits, in the foot-hills and mountains of part
of Virginia, North and South Carolina, and needs only to be taken (the other
parts of the decayed rock included) like sand and shipped to desired places.
As long as the constituent parts of the rock, granite for instance, are in a firm
crystallized state, the alumina forms of course an integral part of the feldspar,
(part of the rock), and is for my purposes unavailable. But when sufficient decay
of the rock has already set in, sufficient to liverate the constituent parts of the
stone, (mainly quarts, feldspar and mica) a contemporary decay of the feldspar
has, as a rule, set in; this leaves free the soda or potash contained in feldspar,
to be washed out by percolating waters; there remaining only silica and alumina.
During this period of decay the alumina is easily acted upon by caustic lime,
as proven by my experiments. The last stage of decomposition of the rock is

page_text: shown, when silica and alumina, remaining in position close together, commence
to form ultimately a hydrous silicate of alumina; in which state its usefulness
for my purpose has ceased.
Mortar produced by my composition and containing aluminum oxide is
especially adapted for use on foundations and especially at places, where periodical
excess of moisture makes it desirable to use a cement that withstands the action
of water. When combined with mica, usually found in great quantities as a
constituent of the deteriorated geneiss, or granite, the mortar becomes an ex-
cellent fireproof material.
Lime (calcium oxide) and aluminum oxide, especially in combination with
mica forms a mortar, which hardens in a short time, is far better to handle with
the trowel than the common lime mortar, and is not as heavy in weight. When
deterioration of granite, etc., has gone so fans to form clay, (a chemically close
combination of alumina and silica) a heating of the clay is necessary to bring
it into a condition to act on lime. Acids, sub-acids, and salts, tending to form
stable combinations insoluble in water with lime and alumina, can be added,
and also improves the consistency and hardness of the mortar.
I desire to have it understood that when I have stated herein that from 1 foot
to 4 cubic feet of aluminum oxide is used in the composition that this quantity
includes the sand, mica or other suitable material that is desirable to mix
with it.
The lime and aluminum oxide may be mixed, or combined together in a dry
state in proper proportions ready for the addition of the water. Therefore, I
desire to claim the combination of the dry ingredients without the water.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. The herein described composition of matter, consisting of water, slaked lime
and bauxite, substantially as described and for the purpose specified.
2. The herein described composition of matter for the manufacture of plaster,
cement, etc., consisting of slaked lime 1 cubic foot, bauxite from 1 to 4 cubic
feet, and a sufficient quantity of pure water to form a plastic or semi-liquid mass,
substantially as described.
3. The herein described composition of matter for the manufacture of plaster,
cement, etc., consisting of slaked lime, bauxite, mica and water, substantially
as described and for the purpose specified.
4. The herein described composition of matter for the manufacture of cement,.
plaster, etc., consisting of slaked lime and bauxite in the proportions specified.
Dated this 13th day of November 1899.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.