Improvements relating to the Setting of Diamonds for Industrial Purposes.
Year: 1898

page_text: Date of Application, 13th Dec., 1898-Accepted, 17th June, 1899
Improvements relating to the Setting of Diamonds for Industrial
Purposes.
I, RICHARD KRAUSE, of No. 8, Neue Oderstrasse, Breslau, Empire of Germany,
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:
-
The present invention consists of a process for setting diamonds for industrial
purposes.
Diamonds, which are set in tools for industrial purposes, are generally encased
in metal so as to prevent the stone which is of itself brittle, from splitting and to
enable its working surface to be applied as conveniently as possible.
The methods hitherto employed consist in encasing the stone in metal by casting
the latter round it or pressing the same round the stone. In both cases the
stone is brought in contact with molten or very hot metal, which has the effect
of injuring it and in most cases rendering it brittle and less durable.
The hermetic enclosure of the stone is difficult to attain by means of the above
mentioned methods, since the cast metal has pores or flaws and the pressed metal
seldom closes on to the very irregular form of the stone, at every point. The metal
oxidizes at the contact surfaces with the diamond at these points.
Thus a very small space remains between the stone and the metal setting which
is filled with a yielding oxide and allows the stone to get loosened when it is
subjected to much wear and tear. This kind of setting does not adequately
protect the stone against splitting. This disadvantage may be characteristically
illustrated by stripping the setting off a stone.
By means of the present process all these difficulties and disadvantages are
avoided and the stone is absolutely hermetically enclosed in the metal setting,
without in any way injuring the diamond.
The process is carried out in the following manner:-
The surfaces of the diamond are first properly cleaned and the stone is then
covered with a metallic precipitation advantageously from silver-salt to render
the diamond conductive by any known chemical process. This precipitation
closes hermetically on to the stone and is then rendered thicker by means of the
well known galvanoplastic process by means of which copper or nickel is coated
onto the silver. The layer of metal thus produced on the stone is then provided
with a thicker coating of metal-bronze or steel-cast on to the same, the casting
taking place advantageously in vacuo, i.e. in an exhausted mould, in order to
attain a pure dense casting, the galvano-plastic layer of metal becoming alloyed
with the metal cast on to the same. The metal mantle produced on the stone
by the galvanic process prevents the stone from coming into direct contact with
the molten metal subsequently cast on the same with which the said layer com-
bines without, however impairing its hermetic closure on to the stone. The metal
layer by means of which the first layer is strengthened combines with the molten

page_text: metal and prevents the destruction or partial destruction of the thin envelopment
of metal first produced.
Since the objects are very small the casting in vacuo can be easily effected in
that the molten metal is allowed to rise in the small mould from which the air
has been pumped out. Diamonds set in this manner will stand a great amount of
wear and tear without getting loose or breaking.
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: Process for setting diamonds for industrial purposes which consists in
first precipitating a thin metal coating on to the stone then strengthening the
same with a coating of metal produced by means of a galvanoplastic process, then
casting a metal setting around the coating thus formed in the manner and for
the purpose, substantially as described.
2: In the process for setting diamonds, set forth in Claim 1, the step which
consists in effecting the casting of the metal setting in vacuo, substantially as
described.
1911
Decombo 1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.