METHOD AND ARTICLE OF MANUFACTURE FOR
IDENTIFYING AND TRACKING ROUGH GEMSTONES
FIELD OF THE INVENTION The present invention relates to the field of marking, identifying, and tracking objects extracted by mining such as uncut or "rough" gemstones or precious metals. More specifically, the present invention relates to a novel method and article of manufacture for encasing an uncut, unpolished, or rough mined object, gemstone, precious metal, or similar materials, within a removable material. Identifiers are branded onto the mined object or applied to the removable material. Identifiers may represent or be encoded with various types of information relating to, for example, the gemstone, gemstone attributes, chain of custody, the owner, or other related information.
BACKGROUND OF THE INVENTION Mined obj ects such as gemstones and precious metals (generally referred to as gemstones for simplicity) are highly valued commodities in both rough (i.e. uncut or unpolished) form and finished form. These objects may be easily transported, sequestered and exchanged. Thus, a method to secure a gemstone and document information such as its genealogy, origin, chain of custody, quality attributes, ownership information, and other types of information, which does not degrade the gemstone, by accepted standards, would be useful and desirable.
A discussion of the geo-political issues concerning the critical need to document the chain of custody and origin of "Conflict Diamonds," i.e., diamonds which have been mined or otherwise obtained by insurgency movements to finance the purchase of arms and supplies, may be found in a publication entitled "Conflict Diamonds: Possibilities for the Identification, Certification and Control of Diamonds," published in June 2000 by the organization Global Witness. This article describes the structure of the international diamond market, the difficulties which exist in determining the origin of diamonds and the currently known technology for the identification of diamonds. Although certain identification methods are known, they primarily require an expert examination of the diamond in question. Such an examination typically involves considerable time and expertise and may well yield inconclusive results. Additionally, a reliable, relatively tamper-proof, cost-effective method, which does not degrade the diamond, by accepted standards, is currently available for identifying rough gemstones.
A viable rough gemstone identification system, to become accepted by a large part of the industry should accomplish the following goals: a. MINIMAL COST: The coding or identification of the rough gemstones, on a per stone basis, should be inexpensive because the code will be removed when the stone is cut and polished.
b. ACCOMMODATES SURFACE IRREGULARITIES: Unlike finished stones cut to somewhat uniform and recognizable shapes, rough gemstones arrive in a plethora of irregular shapes and sizes. A marking and tracking system should tolerate these variables. c. SPEED: Because grading occurs downstream from the extraction of the mined objects such as gemstones, all the rough extracted gemstones should be coded. Considering the volume of rough gemstones which are mined, a time efficient coding process is desirable. d. SIMPLICITY: Again, the volume of extracted rough gemstones may require multiple coding sites or protocols. It is preferable that the coding or identification system be easy to set-up and operate. Also, the maintenance of marking equipment should be within the abilities of employees in the mining industry. e. AVOIDANCE OF DEGRADATION: Those familiar with mining industries will recognize that known processes, including laser engraving of a mark directly onto a mined object or gemstone, such as that taught in U.S. Patent No. 4,392,476 issued to Gessler, photo-etching of a metallic mark taught in U.S. Patent No. 4,056,952 issued to Okuda, or ionized-gas etching of a mark taught in U.S. Patent No.4,425,769 issued to Hakoune, may damage part of the rough gemstone, decrease the value of the rough gemstone, and preclude cuts along the desired or optimum crystal planes.
Accordingly, a method and article of manufacture which accomplishes the above-detailed goals by providing a fast, inexpensive system, which is simple to operate and maintain, accepts a wide variety of types, shapes and sizes of mined objects and does so without degradation to the mined object is desirable.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a simple, inexpensive method and article of manufacture for associating information with mined objects such as rough gemstones and precious metals (generally referred to as rough gemstones). The information may indicate, for example, the source of the gemstone (in the form of a trademark or logo), the grade of the gemstone, the mine from which the gemstone was extracted, the processing which has occurred, the chain of possession, serial number associated with a particular stone, or other related information. For this purpose, gemstones are encased in a removable substance, preferably a polymer. The encasement may be fingerprinted with micro-tags and/or macro-tags and may also be encoded with a laser, ion beam, printer, or other marking device. The encasement substrate is removable and may be re-applied without degrading the encased gemstone. This process can be automated and lends itself to the high speed processing of a large number of mined objects with relatively inexpensive unsophisticated equipment.
According to one aspect of the invention, rough objects and gemstones are first sorted according to pre-determined criteria, weighed, and placed within a compartment of a tray. The
tray may be configured to match with a coordinate transfer system or conveyer belt. A curable polymer is added to each compartment to cover the rough gemstone. Prior to or during curing, micro-tags such as metal oxides or fluorescing dyes may be added to the polymer to create a unique chemical fingerprint. Also, prior to or during curing, macro-tags such as holograms, logos or other easily seen labels may be added to the compartment and embedded in the polymer along with the encased rough gemstone.
According to another aspect of the invention, the encased gemstone can take the form of a hemisphere or other predetermined shape that permits the location of recorded information to be readily determined. Once cured, the encased rough gemstones may be separated from the tray and sorted or placed in the coordinate transfer system for encoding. Encoding of the polymer encasements may be accomplished with a logo, bar-code, or matrix such as those taught in U.S. Patent No. 5,124,536 issued to Priddy, et al, and U.S. Patent No. 5,773,806 issued to Longacre, Jr., et al. A matrix or bar-code may be encoded as a two-dimensional bar-code, a two-dimensional matrix, or a three-dimensional matrix.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram describing encasement of a gemstone;
FIGS. 2A-E are diagrams illustrating one manner of encapsulating gemstones; FIGS. 3A-B are diagrams illustrating another manner of encapsulating gemstones;
FIGS. 4A-B are diagrams illustrating logos or labels affixed to gemstone encasements;
FIG. 5 is a diagram illustrating encoding of gemstone identifiers;
FIGS. 6A-C are diagrams of encapsulated gemstones removed from tray compartments; and FIGS.7A-B are diagrams illustrating reading of the identifier and removal of encasement material surrounding a gemstone.
DETAILED DESCRIPTION
The general encasement and processing techniques are illustrated in Figure 1. In block 100, a rough mined object or gemstone is selected from a mine or point of extraction. In block 110, the rough gemstone is encased. An identifier is applied to the rough gemstone or to the encasement material in block 120. In block 130, if necessary, an identifier is encoded with information relating to the gemstone source, attributes of the gemstone, transaction data, user data, and/or other types of information. When the rough gemstone is identified in block 140 by, for example, a reader or scanner, further processing may be necessary. The encasement may be removed resulting in a free rough gemstone in block 150. Each of these tasks will be described in further detail below with reference to Figures 2-7. The methods and articles described herein
are applicable to a wide range of mined objects of different shapes and sizes. For example, the present invention is applicable to rough gemstones, diamonds, emeralds, rubies, sapphires, crystals (e.g., crystals for watches), pearls, ores, semi-precious stones, minerals, crystals, and other similar materials. However, for simplicity and purposes of illustration, this specification refers to the processing of rough gemstones, and specifically, rough diamonds. Indeed, the present invention is not so limited and may be applied to many other objects and materials. Additionally, the present invention is not limited to encasing rough gemstones. Finished or cut gemstones may be encased and similarly processed.
Encasing Rough Gemstones
Referring to Figures 2A-B, after selecting or retrieving rough gemstones from a mine or point of extraction in block 100, a first encasement material 200 is provided to compartments 210 of a tray 220 into which rough gemstones will be placed. The tray 220 may be of a size and shape to match a coordinate transfer system, such as a conveyer belt, to facilitate efficient rough gemstone processing from the mine, point of extraction, or distribution point. If necessary, the encasement materials may be transparent or translucent to enable the rough gemstone to be visible. The first encasement material 200 is provided to any number of tray compartments 210, depending on the number of rough gemstones to be processed.
One example of a first encasement material 200 is a curable polymer. One example curable polymer that may be utilized results from a combination of a resin and a curing agent such as a hardener or other curing agent such as heat or ultraviolet light. For example, a resin and a hardener manufactured by Tap Plastics, Incorporated, Dublin, California can be combined to form a curable polymer which forms an encasement. The resin used may be a resin with the product name "Tap Plastics Epoxy Resin" or the common name "general purpose 1:1 epoxy". The hardener may be a hardener with the product name "Tap Plastics Epoxy Hardener". The polymer will not degrade the rough gemstone and is added to the tray compartments 210.
Other examples of a first encasement material 200 include various thermoplastics. Many different thermoplastics may be utilized, including but not limited to polyethylene, polybutylene, polycyclohexane, polyphenylene, polycarbonate, polystyrene, polypropylene, polyamide, polyvinylchloride, polyacetal, fluroresins, acrylic resins, and polysulfones, all of which are well known and commercially available from numerous different companies.
Continuing with reference to Figure 2C, the first encasement material 200 is cured resulting in a first cured material 202. As previously explained, different curing techniques may be utilized depending oh the encasement material 200 used. The previously described polymers may be cured with heat. For example, the first encasement material 200 may be heated at about 100 degrees Centigrade for about 30 minutes. After curing, the polymer hardens to the shape of the bottom of the compartment 210. Of course, many different polymers may be cured at
different temperatures for different lengths of time resulting in cured encasements.
Curing may also be performed by removing heat or permitting first encasement material 200 to cool. For example, when thermoplastics cool, they assume the form and shape of their respective molds or tray compartments 210. Additionally, first encasement materials 200 may be cured with radiation or light, e.g.,
"photo-polymers" can be cured with infrared, ultraviolet, or other forms of radiation. After curing, the liquid photo-polymer forms a solid polymer. Indeed, some of the previously mentioned thermoplastics may be used as a photo-polymer with the addition of a photo-initiator. Of course, other curing techniques may be utilized. After the first encasement material 200 is cured 202, referring to Figure 2C, the rough gemstones 230 are placed into compartments 210 of the tray 220. If the cured material 202 is completely cured and solid, the rough gemstone 230 rests on top of the cured material 202. If the cured material 202 is partially cured, then the rough gemstone 230 may settle partially into the partially cured material 202. After placing a gemstone 230 into the compartments 210, in Figure 2D, a second encasement material 240 is added to the compartments 210. The second encasement material 240 partially or completely fills the remaining space in each compartment 210. The second encasement material 240 may be the same as the first encasement materials 200 previously described. In Figure 2E, the second encasement material 240 is cured, resulting in a second cured material 242. The second encasement material 240 may be cured with the curing techniques described with respect to the first cured material 202. The first and second cured material sections 202, 242 form an encasement or casing 244 surrounding the rough gemstone 230.
. Figures 3A-B illustrate an alternative encapsulation technique. In this alternative embodiment, a rough gemstone 330 is surface coated with an encasement material 300. The outer shape of the encasement 310 reflects the topography of the rough gemstone 300 within. As in the previously described technique, an encasement material 310 is cured 302 resulting in an encased rough gemstone 344.
As described in further detail below, various types of information such as a gemstone's genealogy, origin, chain of custody, quality attributes, ownership information, etc. may be embedded into, branded onto, and/or associated with the rough gemstone through chemical fingerprints/identification, affixing labels, logos, or other identification tags to the gemstone or gemstone casing, or encoding identifiers with specific data. The manner in which these identifiers are utilized is described in further detail below.
Chemical Identifiers
If desired, prior to or during curing, a chemical identification tag, fingerprint, impurity,
or additive may be added to encasement materials 200, 240. These chemical additives result in a unique encasement composition or chemical identifier for the rough gemstone 230 encased within the material 244. Duplicating the composition may be difficult, thus providing a further anti-counterfeiting measure. For example, metal-oxides including, but not limited to, TiO2, Cr2O3, and (TiO2 +
Cr2O3) may be added to the encasement materials 200, 240 to create a chemical fingerprint or "micro-tag". Alternatively, fluorescing dyes may provide a unique chemical fingerprint. Examples of fluorescing dyes include metal powders grown under infrared radiation and graphite powders grown under ultraviolet radiation. Other wavelength specific chemical additives may also be incorporated into the encasement materials. For example, ultraviolet or infrared polymers that will glow under specific types or wavelengths of radiation may be deposited within the encasement.
Logo Identifiers Referring to Figures 4A-B, if desired, a "logo" or "macro-tag" 450 may be incorporated into the encasement 444 formed within compartments 410 of the tray 420. The macro-tag 450 may be applied during or after curing 422. The logo 450 may include many different types of information listed above in the form of a physical label, logo, transponder, micro-chip, nano-chip, hologram, text, a mark, a trademark, a number, a serial number, an identification number, a name, a company, an icon, or various other marks or labels. Although Figures 4A-B illustrate a "logo" macro-tag 450, other "macro-tags" 450, including those listed above, may be utilized.
Some macro-tags 450 may store information and require a reading device to interpret the stored information. For example, an infrared or radio-frequency reader may read a transponder, micro-chip, or nano-chip, and display the data stored within the macro-tag 450. Thus, with these macro-tags 450, identification of a gemstone 430 or presentation of related information is simple, fast, and provides a further anti-counterfeiting measure.
Encoded Identifiers
Referring to Figure 5, other data related to the rough gemstone (not illustrated) may be incorporated into an inscribed or identifier 560 with an encoder. The identifier 560 may be branded directly onto a gemstone or affixed to the casing or encasement 544. Identifiers 560 may be used instead of, or in addition to, macro-tags 550. There are various types of identifiers 560 including, but not limited to, a bar-code, a two-dimensional bar-code, a data-glyph, a matrix, and a two-dimensional matrix. Identifiers 560 may be encoded with various types of information as previously described using different devices including, but not limited to, a laser, broad or focused ion beams, reactive ion etching, or a printer.
For example, a laser system such as a Nd: YAG or CO2 laser may be used to inscribe an identifier 560 onto a gemstone or an encasement 544 without damaging the rough gemstone. Laser encoding is also beneficial since it enables automated or semi-automated encoding that may be accomplished by aligning the tray compartments with a transport equipment. Thus, such encoding devices 570 can process a large volume of gemstones in an efficient, automated manner.
As another example, an identifier may be applied to a gemstone or an encasement using reactive ion etching or a broad ion beam. These devices may also be utilized through a mask at the encased gemstone. For more complicated, unique, or individualized encoding, direct write marking may be used. Direct write marking utilizes a high speed laser or focused ion beam which is directed to galvo-scanning mirrors, controlled by a computer-aided design (CAD) software program. The galvo-based system directs the light such that may be utilized. For example, serial numbers or bar-codes can be applied with a direct write marking system. Alternatively, the beam may be stationary and the rough diamond is translated with a stage to produce the desired pattern.
Further, the same marking or identifier may be applied to a plurality of encasements using projection marking or hallmarking by directing light through a mask. The mask can be generated with, for example, CAD programs, and applied to many encasements at a time. The mask used in projection marking may be a non-contact type mask or a contact mask applied to the rough gemstone or encasement. Contact masks may include a metal mask, a chrome on quartz mask, and a dielectric mask.
Also, other exposure or emissions systems may also be utilized including, but not limited to, a broad ion beam, x-rays, electron beam, plasma, and wet/dry chemistry. Further, printers may be used to mark encasements of gemstones. Indeed, various other encoding or marking devices may be utilized.
The marks or identifiers may be used for various purposes. For example, marks may be used to provide different types of information including information relating to the origin, identify, chain of possession, and owner of the gemstone.
To facilitate locating and reading an identifier 560, the identifier 560 may be placed at a predetermined location on the encasement 544. To enable efficient automated processing of gemstones, an identifier 560 reader may be directed to the predetermined location without consuming time locating the identifier 560. As a result, a reader which interprets the identifier 560 may be positioned at the same location of an encasement 544, even if the identifier 560 is not visible to the human eye. For example, in one embodiment, the identifier 560 is placed at the center of a round, flat bottom face 546 of a hemispherical encasement 544. In this embodiment, encased gemstones are positioned such that a reader is applied to the center of the round, flat bottom face 546.
In an alternative embodiment, a mark is applied directly to a gemstone, and the marked gemstone is encased. With this embodiment, the encasement may be made of the same materials and predetermined shapes as previously described. Further, with the predetermined shape serving as a magnifying glass, the mark may be viewed through the encasement / magnifying glass.
Additional enhancements to the automated processing of gemstones may include using a low power focusing laser to target the placement of the encoder 570. This type of machine vision alignment is well known in the art and thus, is not described in detail.
Thus, mined objects and various types of gemstones may be encased, encased and encoded, encased and tagged, or encased, tagged and encoded. After encasing gemstones and applying the desired identifiers to the gemstone or casing, encased gemstones are removed from the tray.
Removing Encased Gemstones From Tray After the encasements 544 are cured, they can be removed from the tray 520. To facilitate quick removal, the tray 520 is constructed of a smooth flexible material from which the encasements 544 may be easily removed by bending or twisting the tray 520.
Referring to Figures 6A-C, the encasements 644 removed from the tray 520 assume the form of tray compartments, e.g., a hemisphere shape 646. The gemstones 630 are encased in encasements 644, along with desired identifiers such as an encoded identifier 660 or a logo 650. Before or after the encasements 644 are removed from the tray, the identifiers branded onto gemstones 630 or onto the encasements 644 may be read by a reader or scanner. The information can be used for purposes of identification, tracking, chain of custody, user data, or other applications.
Reading Identifiers In Gemstone Casing
Before or after the encasements are removed from the tray, the encoded identifiers may be decoded or read such that the desired information is retrieved. Examples of encoded identifier readers include, but are not limited to, a magnifying lens, a bar code reader or scanner, and a matrix reader, depending on the type of identifier used. The shape of an encasement may facilitate the use of different readers.
Referring to Figure 7A, identifiers 760 may be read by various other types of readers 770, depending on the identifier 760 code used. For example, if the identifier 760 is a bar-code, then a bar-code reader or scanner 770 may be used. If the identifier 760 is a matrix, then a matrix reader or scanner 770 may be used. Other readers 770 which may be used include a digital camera connected to a portable computing device or a laser beam scanner.
A magnifying glass, formed by the encasement, may also serve as a reader. Referring
back to Figures 6A-B, the tray compartment, and thus, the resulting shape of gemstone encasement 644, may form a hemisphere 646. The hemisphere 646 may act as a magnifying lens reader to facilitate viewing of an encased rough gemstone 630. The radius of hemispherical compartment 646 may be preselected with a larger radius yielding a lower power magnification or a smaller radius yielding a greater magnification, depending on the requirements of the user.
The encasement 644 is also useful because it is both durable and selectively degradable or removable without damaging the gemstone 630.
Of course, other encasement 644 shapes may be utilized. Although the hemispheric shape
646 of one embodiment provides the useful function of serving as a magnifying lens, compartments of the tray may assume other geometric shapes including but not limited to elliptical, frustoconical, polyconical or pyramidal shapes. These other shapes may also serve to magnify information like a hemisphere.
Referring now to Figures 7A-B, as previously explained, placing the identifier 760 at a predetermined location enables the identifier 760 to be quickly located and read by a reader or scanner 770. The efficiency of reading an identifier 760 is further enhanced by placing the encasement 744 into a base 772 which positions the identifier 760 in the proper orientation for automated reading.
Stripping Agent Referring now to Figure 7B, after the encased gemstones are processed and their respective information is decoded or read for identification, tracking, chain of custody, customer data, or other purposes, the gemstone will eventually be removed from the casing. For example, if the rough gemstone arrives at a diamond processing center, the encasements may be removed such that the rough gemstone can be cut into a number of finished gemstones. Thus, further processing of the rough gemstones 730 may require the encasement 744 to be stripped from the rough gemstone 730. In one embodiment, encasements 744 are removed by applying a solvent or stripping agent 780 to the encasement 744 or submerging the encased rough gemstone 730 in the solvent 780. The solvent 780 should remove or dissolve the encasement 744 material without damaging the gemstone 730. One example solvent for decapsulation of cured epoxy resins is Master Bond MB6 A manufactured by Master Bond, Incorporated of Hackensack, New Jersey. This solvent dissolves the epoxy resin encasement material previously described. For example, a beaker of MB6A is heated to about 100°C, and an encased gemstone is placed in the solvent for about 10 minutes. Thereafter, the encasement will begin to break down, and the gemstone may be removed from the beaker after all of the encasement material is removed. The solvent should not affect the gemstone. If necessary, the gemstone may be re-encased at a future time.
Indeed, there are many combinations of encasement materials and solvents that may be
utilized that do not damage encased gemstones. Thus, the particular example encasement materials and solvents are merely illustrative of many possible combinations.
Certain presently preferred embodiments of apparatus and methods for practicing the invention have been described herein in some detail and some potential modifications and additions have been suggested. Other modifications, improvements and additions not described in this document may also be made without departing from the principles of the invention.