FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
1. Title of the invention: PROCESSING GEMSTONES
2. Applicant(s)
NAME NATIONALITY ADDRESS
SAHAJANAND
TECHNOLOGIES PRIVATE
LIMITED
Indian A1, Sahajanand Estate, Wakharia
Wadi, Near Dabholi Char Rasta, Ved
Road, Surat Gujarat 395004, India
3. Preamble to the description
COMPLETE SPECIFICATION
The following specification particularly describes the invention and the manner in which it
is to be performed.

TECHNICAL FIELD
[0001] The present subject matter relates, in general, to techniques for processing
gemstones.
BACKGROUND
[0002] Generally, unpolished gemstones are subjected to various machining
operations, such as faceting, to obtain polished gemstones. Further, faceting is a
process of creating flat surfaces, called facets, on various portions of the gemstone by
removing excess material from the gemstone. Conventionally, faceting can be
achieved using a laser source that may project a laser beam on an unpolished surface
the gemstone at a predetermined angle. Further, based on the number of facets to be
formed on the gemstone, laser beam may be directed on the different surfaces on the
gemstone.
BRIEF DESCRIPTION OF DRAWINGS
[0003] The detailed description is described with reference to the accompanying
figures. In the figures, the left-most digit(s) of a reference number identifies the
figure in which the reference number first appears. The same numbers are used
throughout the drawings to reference like features and components.
[0004] Fig. 1 illustrates an apparatus for creating facets on a gemstone, in
accordance with an implementation of the present subject matter;
[0005] Fig. 2 illustrates the gemstone showing cutting planes, in accordance with
one implementation of the present subject matter;
[0006] Fig. 3 illustrates a method of creating facets on the rough gemstone, in
25 accordance with one implementation of the present subject matter; and

[0007] Fig. 4 illustrates a non-transitory computer readable medium, according to
an example.
DETAILED DESCRIPTION
[0008] Unpolished or rough gemstones, such as diamonds, 5 are subjected to
various polishing processes, such as sawing, bruting, faceting, conning, or the like to
obtain polished gemstone. During the polishing operation, rough gemstone surface is
processed to form surfaces, such as, table, crown, girdle and pavilion on the rough
gemstone. Conventionally, facets on a rough gemstone, for example, a diamond or a
10 precious or a semi-precious stone, may be processed by directing a laser beam on an
unpolished rough gemstone. Generally, various surfaces of the rough gemstone, such
as table, crown, girdle and pavilion are cut and multiple facets were created on the
rough gemstone surfaces one by one. Such an operation of forming facets is called
faceting operation.
15 [0009] During the faceting operation, the rough gemstone is placed on a holder
and in some case, can be secured to the holder by glue and is positioned with respect
to a laser beam for forming the facets. Further, each facet on the rough gemstone
surface is created by moving the rough gemstone along a predefined axis and
focusing a laser beam on a portion of the rough gemstone surface where the facet is to
20 be formed. For example, the rough gemstone may be translated along a horizontal
axis, such as X-axis to position the rough gemstone in line with the incident laser
beam so that the laser beam can be focused on a portion of the rough gemstone
surface. Once positioned, the laser beam cuts a facet on the portion of the rough
gemstone surface. Once the facet is formed, the rough gemstone is repositioned such
25 that the next portion of the rough gemstone surface is aligned with the laser beam so
that the laser beam can be made incident on the next portion of the rough gemstone
surface. This process is repeated until all facets are formed.

[00010] Conventionally, based on the number of facets to be formed, different
portions of the rough gemstone surface are processed sequentially. For example, for
cutting eight facets, eight different portions of the rough gemstone surface are
processed sequentially. Accordingly, the faceting beings from the first portion and
after the faceting of the first is completed, the faceting of the second 5 portion begins.
In this sequence, the eight portions are faceted. Further, as each facet is cut and some
of the material on the portion of the rough gemstone surface is removed, it results in a
shift of centre of mass of the rough gemstone causing imbalance of the rough
gemstone on the holder. Such an imbalance may cause the rough gemstone to fall
10 from the holder thereby damaging the rough gemstone. In certain cases, the
continuous cutting may remove portions of the rough gemstone whose instantaneous
removal may not be desirable. For example, the laser beam, while continuously
cutting the facet, may inadvertently remove the portion glued to the holder causing
the rough gemstone to fall. In addition, continuous cutting of one portion of the rough
15 gemstone surface at a time may cause overheating of portion of the rough gemstone
surface which may cause damage to the rough gemstone.
[00011] To this end, the present subject matter provides techniques for rough
gemstone processing that allow forming facets on a surface of a rough gemstone. The
technique makes use of an apparatus that includes a rough gemstone holder that holds
20 a rough gemstone and an actuator that provides translational motion to the rough
gemstone holder up to a predefined limit. Further, the apparatus includes a laser
source that incidents a laser beam on a portion of the rough gemstone surface. During
operation, the apparatus cuts the portion of the rough gemstone surface up to a
predetermined depth instead of completely removing the material from the portion of
25 the rough gemstone surface. Once the material up to the predetermined depth is
removed, the rough gemstone is rotated by a predetermined degree and the laser beam
is incident to next portion, such that the laser beam removes the material up to the
predetermined depth. As may be understood, the apparatus based on the present
4
subject matter removes the material homogenously from each portion of the rough
gemstone thereby maintaining the centre of mass of the rough gemstone constant.
Since the material is removed homogenously from all portions of the rough gemstone
surface, the centre of mass of the rough gemstone is maintained thereby keeping
balanced on the rough gemstone on the holder. Moreover, 5 since the material is
removed up to a predetermined depth, inadvertent removal of glue is avoided.
[00012] Techniques based on the present subject matter also prevents damage to
the rough gemstone due to overheating. As may be understood, since one portion is
not removed continuously, the portion being cut is not exposed to laser beam for long
10 time thereby preventing overheating of the rough gemstone. Moreover, during the
repositioning of the rough gemstone, the laser beam is not incident on the rough
gemstone surface thereby allowing dissipation of the heat from the rough gemstone
surface. This further prevents overheating of the rough gemstone.
[00013] These and other advantages of the present subject matter would be
15 described in greater detail in conjunction with the following figures. While aspects of
an apparatus for processing rough gemstone can be implemented in any number of
different configurations, the embodiments are described in the context of the
following device(s) and method(s).
[00014] Fig 1 illustrates an apparatus 100 for processing a rough gemstone 102, in
20 accordance with an implementation of the present subject matter. The apparatus 100
includes a holder 104, an actuating device 106, a laser source 108, a first beam
orientation device 112, a lens 114, a second beam orientation device 118, an image
capturing device 120, and a controller 122.
[00015] According to the illustrated aspect, the holder 104 holds the rough
25 gemstone 102 to create facets on a rough gemstone surface. The surface includes a
crown, a girdle, or a pavilion. For processing different surfaces of the rough gemstone
102, the holder 104 may hold the rough gemstone 102 at different orientations. For
5
example, for creating facets at the crown on the surface of rough gemstone 102, the
holder 104 may hold the rough gemstone 102 upright to keep the crown surface at the
top and pavilion surface at the bottom. In another example, for creating facets at the
pavilion of the surface of the rough gemstone 102, the holder 104 may hold the rough
gemstone 102 in an inverted position to keep the pavilion surface 5 at the top and the
crown surface at the bottom. Although the subject matter has been described with
reference to specific embodiments, this description is not meant to be construed in a
limiting sense. In one example, the actuating device 106 is coupled to the holder 104
by a shaft (not shown in Fig. 1). Further, the actuating device 106 controls the
10 movement of the holder 104 and the rough gemstone 102. In an example
implementation, the holder 104 is coupled to a plurality of actuating devices 106
where each of the actuating devices 106 is to translate the rough gemstone 102 in a
horizontal plane or a vertical plane or to tilt the rough gemstone.
[00016] According to an aspect, the laser source 108 generates a laser beam 110 to
15 process the rough gemstone 102. The first beam orientation device 112 delivers the
laser beam 110 from the laser source 108 towards the rough gemstone 102, as shown
in Fig. 1. The first beam orientation device 112 may be partially mirrored. For
example, the first beam orientation device 112 can be a glass coated with a reflective
layer that may reflect the laser beam 110 and may also allow lights of other
20 wavelengths to pass through it. Further, the lens 114 is installed to focus the laser
beam 110 directed from the first beam orientation device 112 on a surface of the
rough gemstone 102. As shown in Fig. 1, the lens 114 is arranged over the holder 104
and the holder 104 is arranged over the actuating device 106. The arrangement makes
the laser beam 110 incident over the rough gemstone 102. The laser source 108, first
25 beam orientation device 112 and the lens 114 are fixed in the apparatus 100. As a
result, the focus of the laser beam 110 is also fixed at a focal point below the lens
114. The actuating device 106 positions the rough gemstone 102 such that the laser
6
beam 110 is incident on a surface of the rough gemstone 102 and cuts specific
portions on the surface of the rough gemstone 102 to obtain facets.
[00017] According to the illustrated aspect, the controller 122 includes
processor(s) which may be implemented as microprocessors, microcomputers,
microcontrollers, digital signal processors, central processing 5 units, state machines,
logic circuitries, and/or any devices that manipulate signals based on operational
instructions. Among other capabilities, the processor(s) may fetch and execute
computer-readable instructions stored in a memory (not shown) coupled to the
processor(s) of the controller 122. The memory may include any non-transitory
10 computer-readable storage medium including, for example, volatile memory (e.g.,
ram), and/or non-volatile memory (e.g., eprom, flash memory, nvram, memristor,
etc.). The memory may be internal or external to the controller 122. The functions of
the controller 122 may be provided through the use of dedicated hardware as well as
hardware capable of executing computer-readable instructions. The controller 122 is
15 coupled to the actuating device 106. The controller 122 provides signals to the
actuating device 106 to control the movement of the holder 104 which further
controls the movement the rough gemstone 102. The controller 122 signals the
actuating device 106 to reciprocate the rough gemstone 102 in the horizontal plane,
i.e. Along x-axis or along y-axis.
20 [00018] In operation, the controller 122 actuates the actuating device to move the
holder in order to align each portion at the predefined orientation with respect to the
laser source. In addition, the controller 122 actuates the laser source to remove
material from the aligned portion up to a first predetermined depth extending between
a surface of each portion and before an imaginary sawing plane passing through the
25 rough gemstone. Moreover, the controller 122 actuates the laser source 108 to remove
material from the aligned portion up to a second predetermined depth that extends
from a sawed surface of the portion formed upon removal of material up to the first
predetermined depth and the imaginary sawing plane. In one example, the first
7
predetermined depth and the second predetermined depth can be any depth extending
from the surface into the rough gemstone 102, such that the removal of material from
the rough gemstone 102 up to the depth does not affect the centre of mass of the
rough gemstone thereby ensuring that the rough gemstone 102 does not fall from the
5 holder 104.
[00019] According to the illustrated implementation, the second beam orientation
device 118 and the image capturing device 120 enables the operator to observe the
rough gemstone 102 while the rough gemstone 102 is mounted on the holder 104 or
processed by the laser beam 110. The second beam orientation device 118 directs a
10 light 116, reflected from the rough gemstone 102 and passing through the lens 114
and the first beam orientation device 112, towards the image capturing device 120.
The reflected light 116 may be captured by the image capturing device 120 to
generate images that may be observed by the operator to monitor the processing of
the rough gemstone 102. In an example implementation, the second beam orientation
15 device 118 can be, but not limited to, a mirror, a triangular prism, a pentaprism, or the
like. The second beam orientation device 118 may reflect the light of all wavelengths.
In an example implementation, the image capturing device 120 may be, but not
limited to, a camera. In an example implementation, the image capturing device 120
may have 15 light filters that may filter stray lights from entering into the image
20 capturing device 120.
[00020] Fig. 2 illustrates the rough gemstone 102 along with the planes that are
taken as references for cutting the rough gemstone 102. As illustrated the rough
gemstone 102 is a rough gemstone placed on the holder 104 and is secured to the
holder 104 by glue 202. Further, a shape of the polished rough gemstone 204 is also
25 illustrated inside the rough gemstone 102. As shown in fig. 2, a portion of the rough
gemstone surface is to be cut along an imaginary plane a-a, called as imaginary
sawing plane. Further, as illustrated, the imaginary plane a-a also cuts through a
portion glued to the holder and if the laser beam 110 cuts through this region, the
8
rough gemstone 102 gets imbalanced and may fall off the holder 104. However, in
case of the present subject matter, the rough gemstone 102 is placed in such a manner
the laser beam does not cut along the imaginary sawing plane A-A completely but
removes the material up to first a predetermined depth before the imaginary sawing
plane A-A. As a result, not all material is removed 5 that otherwise would have
removed if the rough gemstone 102 is cut along with the imaginary sawing plane A-A
resulting in change in centre of mass that can lead to rough gemstone 102 falling
from the holder 104.
[00021] The operation of the apparatus 100 will now be described. At the
10 beginning of the operation, the rough gemstone 102 is placed on the holder 104. In
one example, the rough gemstone 102 may be glued to the holder 104. Once the
rough gemstone 102 is placed, the controller 122 actuates the actuating device 106 for
moving the holder 104 and the rough gemstone 102 along a horizontal axis, such as
x-axis, by a predefined displacement such that a portion of the rough gemstone
15 surface is positioned in line of the laser beam 110. Further, the rough gemstone 102 is
placed such that when the laser beam is made incident on the portion of the rough
gemstone surface, the laser beam only removes material from the portion up to a
predetermined depth. After the rough gemstone 102 is positioned, the laser beam 110
is made incident on the portion of the rough gemstone surface and the laser beam
20 removes some of the material from the portion of the rough gemstone surface. Once
the material is removed, the rough gemstone 102 is rotated by a predetermined angle
and translated up to the predefined displacement such that the next portion of the
rough gemstone surface is aligned in same orientation as the previous portion of the
rough gemstone surface. Once aligned, the laser beam 110 is focused on the next
25 portion and the same amount of material is removed from the next portion. This
process repeated until all portions of the rough gemstone surface is processed.
Thereafter, the actuating device 106 translate the rough gemstone 102 by a second
predefined displacement so that the laser beam 110 can remove the material at a
9
greater depth that the previous predetermined depth. This operation is repeated until
the all facets are formed.
[00022] The present subject matter also relates to a method of processing the rough
gemstone 102. Fig. 3 illustrates an example method 300 for forming facets on the
rough gemstone according to an implementation of the present 5 subject matter. The
method 300 may be described in the general context of computer executable
instructions. Generally, computer executable instructions can include routines,
programs, objects, components, data structures, procedures, engines, functions, etc.,
that perform particular functions or employ particular abstract data types. The method
10 may also be practiced in a distributed computing environment where functions are
performed by remote processing devices that are linked through a communications
network. In a distributed computing environment, computer executable instructions
may be located in both local and remote computer storage media, including memory
storage devices.
15 [00023] The order in which the method is described is not intended to be construed
as a limitation, and any number of the described method blocks can be combined in
any order to employ the method 300, or an alternative method. Additionally,
individual blocks may be deleted from the methods without departing from the spirit
and scope of the subject matter described herein. Furthermore, the methods 300 can
20 be employed in any suitable hardware, software, firmware, or combination thereof.
The method 300 is explained with reference to the apparatus 100, however, the
methods can be employed in other systems as well.
[00024] Initially, at block 302, the rough gemstone 102, that includes the plurality
of portions, may be placed on the holder 104. Thereafter, at block 304, the controller
25 122 actuates the actuating device 106 to impart both translation motion either along
the X-axis or the Y-axis and rotational motion to one portion of the rough gemstone
102 is sequentially positioned at the predetermined orientation with respect to the
laser source 108. Once positioned, at block 306, the laser beam 110 is made incident
10
on one portion upon alignment to remove the material from the rough gemstone
surface up to the predetermined depth that extends from a surface of the aligned
portion and before the imaginary sawing plane A-A. Once the material up to the
predetermined depth is removed, the rough gemstone 102 is repositioned such that
the laser beam 110 is now incident next portion of the rough 5 gemstone surface and
the laser beam 110 can remove material from the next portion up to the
predetermined depth. Thereafter, the laser beam 110 removes the material from the
next portion up to the predetermined depth. This process is repeated until all the
portions are removed. Once the material is removed, the portion which was first
10 aligned with respect to the laser source 108 is positioned again at the predefined
orientation. Thereafter, the controller 122 actuates the laser source 108 to direct the
laser beam 110, such that the laser beam 110 removes material from the portion up to
a second predetermined depth that extends from a sawed surface of the portion
formed upon removal of material up to the first predetermined depth and the
15 imaginary sawing plane A-A. Further, this process is repeated for each portion is
repeated and the depth is further increased until the facets are formed.
[00025] FIG. 4 illustrates an example network environment 400 using a nontransitory
computer readable medium 402 to assign the mobility factor, according to
an example of the present subject matter. The network environment 400 may be a
20 public networking environment or a private networking environment. In one example,
the network environment 400 includes a processing resource 404 communicatively
coupled to the non-transitory computer readable medium 402 through a
communication link 406.
[00026] For example, the processing resource 404 may be a processor of a
25 computing system, such as the controller 122. The non-transitory computer readable
medium 402 may be, for example, an internal memory device or an external memory
device. In one example, the communication link 406 may be a direct communication
link, such as one formed through a memory read/write interface. In another example,
11
the communication link 406 may be an indirect communication link, such as one
formed through a network interface. In such a case, the processing resource 404 may
access the non-transitory computer readable medium 402 through a network 408. The
network 408 may be a single network or a combination of multiple networks and may
use a variety of communication 5 protocols.
[00027] The processing resource 404 and the non-transitory computer readable
medium 402 may also be communicatively coupled to data sources 410 over the
network 408. The data sources 410 may include, for example, databases and
computing devices. The data sources 410 may be used by the database administrators
10 and other users to communicate with the processing resource 404.
[00028] In one example, the non-transitory computer readable medium 402
includes a set of computer readable and executable instructions, such as the engines
210. The set of computer readable instructions, referred to as instructions hereinafter,
may be accessed by the processing resource 404 through the communication link 406
15 and subsequently executed to perform acts for network service insertion.
[00029] For discussion purposes, the execution of the instructions by the
processing resource 404 has been described with reference to various components
introduced earlier with reference to description of FIG. 1 and 2.
On execution by the processing resource 404, the controller 208 may the
20 controller, operates the apparatus 100 to process the rough gemstone 102 as described
above. For instance, the controller 208 may actuate the actuating device 106 to at
least one of a translation motion and a rotational motion to the holder to align each
portion from amongst the plurality of portions at a predefined orientation with respect
to a laser source. In addition, the controller 122 actuates the laser source 108 to direct
25 laser beam 110 at each portion upon alignment to remove material from the portion
up to a predetermined depth extending between a surface of each portion and before
an imaginary sawing plane passing through the rough gemstone.
12
[00030] Although the above example implementation is explained with respect to
faceting process up to a predetermined limit, the apparatus 100 may also be used for
conning process. During the conning process, rough gemstone 102 is secured to the
holder 104 and one pavilion of the rough gemstone 102 is cut up to a predetermined
limit. Thereafter, the actuating device 106 rotates the rough 5 gemstone 102 by a
predetermined degree so that the laser beam removes some material from another
portion of the pavilion. Once the material is removed, the rough gemstone 102 is
rotated and the next portion of the pavilion is aligned with the laser beam 110. This
operation is repeated until facets are formed on the pavilion.
10 [00031] Various modifications of the disclosed embodiments, as well as alternate
embodiments of the subject matter, will become apparent to persons skilled in the art
upon reference to the description of the subject matter. It is therefore contemplated
that such modifications can be made without departing from the scope of the present
subject matter as defined.
13
I/We Claim:
1. An apparatus (100) for forming facets on a rough gemstone (102) having a
plurality of portions, the apparatus (100) comprising:
a holder (104) to hold the rough gemstone (102);
a laser source (108) to incident a laser beam on the rough 5 gemstone (102);
an actuating device to impart at least of a translational motion and a rotational
motion to the holder (104) to position the rough gemstone (102) at a predefined
orientation with respect to the laser source (108);
a controller (122) coupled to actuating device and the laser source (108) to
10 process each of the plurality of portion, wherein the controller (122) is configured to:
actuate actuating device to move the holder (104) to align each portion
at the predefined orientation with respect to the laser source (108);
actuate the laser source (108) to remove material from the aligned
portion up to a first predetermined depth extending between a surface of each
15 portion and before an imaginary sawing plane passing through the rough
gemstone (102).
2. The apparatus (100) as claimed in claim 1 further comprises a first beam
orientation device to incident the laser beam on the rough gemstone (102).
3. The apparatus (100) as claimed in claim 1 further comprises an image
20 capturing device (120) to capture light reflected by the rough gemstone (102) and a
second beam orientation device (118) to reflect the light reflected by the rough
gemstone (102) towards the image capturing device.
4. A method of forming facets on a rough gemstone having a plurality of
gemstone, the method comprising:
25 mounting a rough gemstone on a holder, the rough gemstone having a
plurality of portions;
14
imparting at least one of a translation motion and a rotational motion to the
holder to align each portion from amongst the plurality of portions at a predefined
orientation with respect to a laser source
directing a laser beam at each portion upon alignment and removing material
from the portion up to a first predetermined depth extending 5 between a surface of
each portion and before an imaginary sawing plane passing through the rough
gemstone.
5. The method as claimed in claim 4 further comprising:
positioning each of the plurality of portions at the predefined orientation with
10 respect to the laser source and directing the laser beam at each portion upon
alignment and removing material from the portion up to a second predetermined
depth extending between a sawed surface of each portion formed upon removal of
material up to the first predetermined depth and the imaginary sawing plane passing
through the rough gemstone.
15 6. The method as claimed in claim 4, wherein material is removed in a way that
a centre of mass of the rough gemstone (102) is constant during removal of material.
7. A non-transitory computer-readable medium comprising computer-readable
instructions for forming facets on a rough gemstone (102), having a plurality of
portions, mounted on a holder (104) using glue, when executed by a processing
resource, cause the processing resource to:
impart, by an actuating device (106), at least one of a translation motion and a
rotational motion to the holder to align each portion from amongst the plurality of
portions at a predefined orientation with respect to a laser source;
direct, by a laser source (108), at each portion upon alignment and removing
material from the portion up to a predetermined depth extending between a surface of
each portion and before an imaginary sawing plane passing through the rough
gemstone.