DEVICE FOR VERIFYING GOLD AND SILVER AUTHENTICITY

Field of the Invention

This invention relates to an apparatus that combines four testing methods that can be carried out on a piece of bullion/ precious metal to verify its authenticity. These methods can be applied to bars or coins.

Background to the Invention

The authenticity of bullion and precious metals can be determined by using various methodologies such as measuring density, weight, volume, resonance of sound, eddy currents, and conductivity.

Precious metals can be distinguished by their unique densities. However, by the mixing of metals of higher and lower densities, it is possible to replicate these densities using proportions of different metals. The measurement of densities forms an essential part of any comprehensive test.

The inexpensive availability of high sensitivity scales (to 0.001 of a gram) makes measuring the weight straight forward. These scales are generally calibrated using a fixed weight, compensating for any variations in environmental factors and locations.

To measure volume, there are various techniques available. For investment grade bullion, the dimensions are well-known and published by the respective manufacturers. Other techniques can be easily used such as the famed Archimedes principle, or the use of callipers to measure dimensions. The method outlined in this application seeks to take advantage of the fixed dimensions in which the bullion is supplied from the manufacturers.

The resonance of sound in bullion can be measured, and there are multiple apps available where a piece of bullion can be identified by the sound it makes under a particular sound test. For example, www.thefisch.com has a commercially available ringer that applies a fixed impact to various coins, the sound is authenticated by comparison with an authentic piece of bullion, or directly by the user familiarity with the expected sound of an authentic piece of bullion. Tests are performed by either tapping the coin with another coin, or dropping the coin onto a wooden or metallic surface to establish the sound that comes from it. More recently the sound is recorded, and the sound waves are analysed using Fast Fourier Transforms and mapped to known Bullion databases to check for authenticity. A specific piece of bullion makes a specific sound due to its composition and its topology; these are not considered conclusive tests but are valuable in identifying counterfeits. Conductivity is the inverse of resistivity and that these are unique properties attributable to all metals. An eddy current is a current that is induced in a conductive material due to a moving magnetic field. This is described by “Faraday's law of induction”. Eddy currents flow in closed loops within conductors in planes perpendicular to the magnetic field. When a conducting body is in the presence of a moving magnetic field, (or vice versa as the motion is relative), the moving body experiences a force in the opposite direction to which it is moving.

Another method used is described in US10497198B2, which uses a coin slide. The patent describes the terminal velocity of a coin as it descends the slide. The coin slides on the market put this effect to good use by sliding the coin down a sloped face, the sloped face is layered with magnetic plates that alternatively have their north poles outward or inward to the plane of motion of the coin.

Conductivity tests can be used as any piece of metal can be tested for its conductivity. However, this is a more expensive test, this can only be done using specialized and expensive equipment at present.

Spectroscopy can also be used to determine the authenticity of bullion and precious metals. However, this again involves specialized and expensive materials.

DE202016005216U discloses devices for the non-contact analysis of precious metals, and precious metal mouldings based on their diamagnetic properties, in particular of gold and silver coins and gold and silver bars, the device comprising (a) a flat, horizontal base plate, (b) at least one vertical frame part arranged perpendicular thereto, (c) a swingable pendulum body, preferably a pendulum rod, a permanent magnet is attached to the lower end of the pendulum body, and the height of the pendulum body is adjustable so that the magnet is a short distance above a precious metal sample, which is exactly in the rest position of the pendulum body below this can swing (see [0012] and Claim 1 ).

DE202017000326U describes a multi-test device for testing precious metal mouldings (coins and bars) that can be used universally by laypeople as well as traders and that tests the entire moulding. The measuring attachment is a vertically moving rod having a magnet, and preferably a neodymium magnet.

FR3007141 A1 describes a device for controlling the metallurgical purity of gold objects, such as bars or ingots, using a means for measuring the forces caused by the induced currents generated by the passage of these objects in a magnetic field produced by magnets, a calculation means for calculating the value of the forces caused by the passage of objects of the same dimension, passing to the same position, and of conduction equal to that of gold. A digital camera or scanner or a piezoelectric sensor is used to measure the force changes in the magnetic field.

DE202012006143U describes a device for checking the authenticity of precious metal mouldings, in particular gold and silver coins and gold and silver bars. The measurement is based on the different magnetic susceptibility of the precious metals gold and silver (diamagnetism) to tungsten, tantalum and nickel. The device used incorporates a frame holding a threaded rod, a cylinder with a threaded hole on the threaded rod, and a strong neodymium-based disc magnet embedded in the cylinder and fastened.

It is the object of the subject application to overcome at least one of the above-mentioned problems.

Statement of Invention

The invention is primarily concerned with the validation of investment grade bullion and precious metals. However, the techniques described here could be used for all precious metals of lower grade than what is considered investment grade. Giving a visual representation of the relationship between the conductivity of the metal and the movement of a magnetic pendulum over a sample, the device can be used for comparing this property of the bullion sample to other verified bullion test results.

The invention relates to a method of differentiating bullion from counterfeit bullion, without causing any damage to the bullion being tested, and can be used on bullion without removing any packaging. The method fulfils this need by employing conventional and novel equipment to establish the measurement of four features of the bullion. The four features are as follows:

(1 ) The weight of the bullion.

(2) The volume of the bullion.

(3) Using an apparatus described herein, the effect of the bullion on the period, amplitudes and number of oscillations and/or the position of a magnetic pendulum in motion above it when placed in the apparatus, in particular the effect on the number of oscillations for one complete motion of the pendulum from release to the pendulum coming to rest.

(4) The sound that the bullion makes under a standard “knock” from the pendulum hitting it. The results of these experiments can be used to determine the authenticity of the sample of a piece of bullion when compared to the results obtained when using a verified reference piece of bullion.

The device of the claimed invention comprises a box, containing a pendulum on which the pendant is a neodymium magnet, a smart device holder and a sensitive scale holder as well as a place holder into which a platform which contains the bullion during the magnetic test is placed.

There is provided a device comprising a housing, the housing having at least three walls, a base and a crossbeam secured to at least two walls, wherein the base further comprises a mould configured to accommodate a test sample or reference sample, and a pendulum pivotally secured to the crossbeam, the pendulum comprising a rod having a magnet affixed thereto, wherein the device further comprises a printed circuit board incorporating an accelerometer, an accurate close-loop triaxial gyroscope, a triaxial geomagnetic sensor and a microcontroller. In one aspect, the printed circuit board incorporating an accelerometer, and/or gyro and optionally a magnetometer and a microcontroller is contained in the enclosure that rotates around the crossbeam.

The pendulum further comprises a neodymium magnet, with fixed parameters to produce dampened oscillations, which can be compared to other verified reference pieces of bullion having undergone the same test. The movement of the pendulum can be observed and recorded using various means, it can be visually observed and counted or recorded using a smart device for analysis, which is accommodated in a fixed smart device holder that can be reversibly attached to the device.

The period, amplitude, and number of the oscillations of the pendulum can be analysed from data stored on the smart device. The number of oscillations is proportional to the volume and conductivity of the precious metal in the bullion sample. Since the volume can be measured and is fixed, the conductivity of the precious metal can be compared with known authentic reference articles of the same manufacture and specifications.

There is provided, as set out in the appended claims, device (1 ,100,200) for determining the authenticity of a test bullion sample, the device (1) comprising: a base (56), a platform (4,40) adapted to accommodate a test bullion sample, and a pendulum (11), the pendulum (11) comprising a rod (12) pivotally connected to a crossbeam (30) by a pivot point (7), and a magnet (3), wherein the magnet (3) is at a distal end (14) of the rod (12) and the pendulum (11 ) is connected to the pivot point (7) at its proximal end and held stationary by a release switch (2); wherein when the pendulum (11 ) is released from the release switch (2) the number of oscillations of the pendulum (11 ) is measured, and the number of oscillations determines the authenticity of the test bullion sample by comparing the number of oscillations measured for the test bullion sample against the number of oscillations measured for a reference bullion sample; and wherein when the pendulum (11 ) is released by the release switch (2) the pendulum (11 ) moves in an x-y plane of fixed constraint.

In one aspect, the device (100,200) further comprises a printed circuit board configured to measure at least one parameter selected from angular acceleration, angular velocity, orientation, and absolute orientation of the pendulum (11 ) in relation to the bullion sample accommodated in the platform (4,40). In one aspect, the printed circuit board comprises one or more components selected from an accelerometer, a closed loop triaxial gyroscope, a triaxial geomagnetic sensor and a microcontroller.

In one aspect of the device (200), the printed circuit board is incorporated in the base (56).

In one aspect of the device (100), the printed circuit board is incorporated in a housing (21 ) which envelopes the crossbeam (30). As mentioned above, the printed circuit board comprises one or more components selected from an accelerometer, a closed loop triaxial gyroscope, a triaxial geomagnetic sensor and a microcontroller. The gyroscope and accelerometer are attached to the housing that is attached the pendulum. When the crossbeam rotates with the swinging of the pendulum, the housing rotates around the crossbeam, and the components on the printed circuit board, such as the gyroscope, accelerometer, etc., measure this movement.

In one aspect, the device (200) further comprises a first support beam (84) and a second support beam (86), and a first stanchion (81 a) and a second stanchion (81 b), wherein the first stanchion (81 a) and the second stanchion (81 b) are also joined to the first support beam (84) and the second support beam (86), respectively. Preferably, the device (200) further comprises a crossbeam (85a, 85b) substantially parallel to the base (56), wherein the crossbeam (85a) is joined to the first stanchion (81 a) and the first support beam (84), and wherein the crossbeam (85b) is joined to the second stanchion (81 b) and the second support beam (86). Preferably, for the device (200), the release switch (2) is located on the crossbeam (85a, 85b) or on the first or the second stanchion (81 a, 81 b).

In one aspect of the device (200), the release switch (2) further comprises an overshoot stud (82) and a restraining stop (83) configured to set an activation position B of between about 45° to about 90° relative to the vertical axis. Preferably, the activation position B is between about 50° and about 80° relative to the vertical axis. Preferably, the activation position B is between about 55° and about 75° relative to the vertical axis. Preferably, the activation position B is between about 60 ° and about 70 ° relative to the vertical axis. Ideally, the activation position B is about 55 relative to the vertical axis.

In one aspect, the device (200) further comprises a laser (210) adapted to register an oscillation of the pendulum (11 ) when the pendulum (11 ) breaks a laser beam generated by the laser (210). Preferably, the laser beam (210) is in communication with a microprocessor adapted to record each oscillation.

In one aspect, the printed circuit board further comprises a photoelectric sensor, such as a thru beam sensor, retro reflective sensor or a diffuse reflective sensor.

In one aspect, the device (1 ,100) further comprises a housing (50) comprising at least three walls (52,53,54,55), and wherein the release switch (2) is located on any one of the walls (52,53,54,55).

In one aspect, the release switch (2) is located on any one of the walls (52,53,54,55); preferably on the wall (52); more preferably on the wall (53); and ideally on the wall (54). In one aspect, the release switch (2) is located at the junction between the wall (53) and the wall (54).

In one aspect, the printed circuit board further comprises a photoelectric sensor, such as a thru beam sensor, retro reflective sensor or a diffuse reflective sensor.

In one aspect, the magnet (3) faces down towards the base (26) and the platform (4,40).

In one aspect, the pendulum (11 ) pivots from the crossbeam (30) in a planar motion.

In one aspect, the pendulum (11 ) hangs freely when at rest.

In one aspect, the magnet is selected from a manganese-aluminium magnet, a neodymium magnet, a neodymium-iron-boron magnet, a samarium-cobalt magnet, an iron ore magnet, a cobalt magnet, a nickel magnet, and a ferrite magnet, or a combination thereof.

In one aspect, the magnet (3) is removable.

In one aspect, when the magnet (3) is removed from the rod (12), the rod (12) is covered with a protective sheath.

In one aspect, the housing (50) further comprises a front fagade hingedly attached to the wall (53).

In one aspect, the platform (4,40) further comprises at least one groove adapted to accommodate the test bullion sample in an upright position. In one aspect, the base (56) further comprises an oscillation counter.

In one aspect, the device further comprises a holder adapted to accommodate a recording device. Preferably, the recording device is a smart phone, a microphone, a camera, an acoustic sensor, a video capture device.

In one aspect, the device (1 ,100,200) further comprises a sample dimension apparatus (150), the apparatus (150) comprising a plurality of slots (152) adapted to hold a plurality of test bullion samples. Preferably, each of the plurality of slots (152) are configured to accommodate a test bullion sample with a particular thickness and diameter.

In one aspect, the apparatus (150) is adapted to test at least 36 of the most popular coins on the market. The plurality of slots (152) can accommodate the at least 36 coins and can also accommodate a wide range of other coins, which can be referenced through the reference indicators A1 through to D9 as shown in Figure 4. The apparatus (150) is very flexible to cover a broad range of coins on the market.

In one aspect, there is provided a system for authenticating a test bullion sample, the system comprising:

(i) placing the test bullion sample into the platform (4) of the device (1 ,100,200) as described above;

(ii) activating the release switch (2) such that the pendulum (11 ) moves freely over the test bullion sample;

(iii) recording the movement of the pendulum (11 ) over the test bullion sample and comparing the movement of the pendulum (11 ) over the test bullion sample against the movement of the pendulum (11 ) over a reference bullion sample stored in a database and determining whether the test bullion sample is authentic.

In one aspect, the system further comprises the step of performing a standard knock test on the test bullion sample and recording the sound made from said knock. Preferably, the knock test is performed when the magnet (3) is removed from the rod (12) and the rod (12) is covered with a protective sheath.

In one aspect, the system further comprises a sample dimension apparatus (150), the apparatus (150) comprising a plurality of slots (152) adapted to accommodate a test bullion sample. Preferably, each of the plurality of slots (152) are configured to accommodate a test bullion sample with a particular thickness and diameter. Definitions

In the specification, density = mass/volume. While mass and weight are different, weight = mass * gravity for the purpose this document, and in common use they are used interchangeably.

In the specification, the term “crossbeam” should be understood to mean a support structure that spans between two or more elements, for example, from the upper portion of one wall of the housing to the upper portion of another (parallel) wall of the housing, or between a pair of bearing encasement structures, or between the release switch and an overshoot stud. The crossbeam is typically positioned equidistant between the elements and is adapted in one instance to pivotally hold the pendulum such that the pendulum hangs from the crossbeam and is centrally over the mould the device when at rest.

In the specification, the term “release switch” should be understood to mean a mechanism by which the pendulum is released from its resting position and allowed to swing back and forth over the test bullion sample in the mould or platform of the device of the claimed invention.

In the specification, the term “knock test” should be understood to mean that when the pendulum rod is released by the release switch, the pendulum strikes the bullion sample, which will result in a sound when the pendulum rod contacts the bullion. The sound can then be recorded using a sensor or smart device and analysed against the sound of a reference bullion undergoing the same test. It should be noted that the pendulum rod does not damage the bullion during this test.

In the specification, the terms “pit”, “platform”, and “mould” should be understood to mean a means by which the test and reference bullion samples are held in place in the device during the testing process. The terms can be used interchangeably. Typically, the pit is a tray-like means that can accommodate any shape of bullion; the mould is a configured to accommodate a particular shape of bullion; and the platform is configured to accommodate bullion having different shapes and dimensions. It should also be noted that the pit, platform and mould can be removed from the device of the claimed invention if required.

In the specification, the term “sensor fusion” should be understood to mean the process of merging data from multiple sensors or data derived from disparate sources such that the amount of uncertainty that may be involved is reduced when these sources are used individually. For instance, one could potentially obtain a more accurate location estimate of an indoor object by combining multiple data sources such as video cameras and WiFi® localization signals.

In the specification, the term “printed circuit board” should be understood to mean a laminated sandwich structure of conductive and insulating layers comprising a plethora of components. For example, on a standard nine-axes degrees of freedom board, such components include a gyroscopic sensor, an accelerometer, a magnetometer, a microcontroller, a WIFI® module, A Bluetooth® module, a multitude of diodes, resistors, and the like.

Brief description of the drawings

The invention will be more clearly understood from the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which

Figure 1 illustrates a perspective view of one embodiment of the device of the present invention, connected to a smart device.

Figure 2 illustrates (a) a side view of one embodiment of the device of the present invention; (b) is a front view of the device of (a); and (c) is a top view of the device of (a) and (b).

Figure 3 is a graph illustrating a free set of oscillations in the absence of any bullion, a reference bullion and a fake bullion sample. The test measures the angle of orientation against the time axis, the time axis being the x axis in the graph, and the angle of orientation is represented as the y axis. Three independent sets of test results are shown and compared to each other. The outer envelope represents the motion of the pendulum in two dimensions, without the influence of any bullion, only acting under gravity and the friction components. As the pendulum oscillates, it carves out the wave pattern as depicted in Figure 3 (see baseline). The authentic sample used here is an American Gold Eagle 1 Troy Ounce coin (2008) and the fake sample used is a high-quality counterfeit American Gold Eagle 1 Troy ounce of the same weight, dimensions, look and feel. The fake sample is composed of a tungsten core with gold plating. The wave patterns carved out by the motion of the pendulum are distinctly different and easily identifiable.

Figure 4 illustrates a sample dimension apparatus used in conjunction with the device of the claimed invention.

Figure 5 illustrates one aspect of the device of the invention where the pendulum is set at the rest position A and engaged with an element of the release switch at position B. Position B is the initial launch angle of the pendulum. The pendulum is held at position B by the release switch. The release switch is activated, and the stop is pulled outwards relative to the housing of the device, releasing the pendulum to swing and carry out the test. The device measures and displays the result of the pendulum oscillations entirely on the device with no transmission of data to the account of the customer from the device. This allows the customer the security of operating the test completely offline. A laser is positioned at the neutral or resting position A of the pendulum. When the pendulum is released by the release switch and begins its path of oscillations over the bullion, the number of oscillations of the pendulum is recorded when the pendulum breaks the laser beam, and the data is stored and processed in a printed circuit board in the base of the device. After undergoing any calibration adjustments in the microcontroller, the data is displayed directly to counter on the base of the device. Detailed description of the Fiaures

The device of the claimed invention provides a magnetic pendulum that is constrained to move in two dimensions over the bullion surface. The change in velocity of the pendulum is a function of the surface area of the bullion being tested. As such the magnet must traverse a repeatable motion over the bullion to compare results from one test to another. The constraint of the motion of the pendulum in two dimensions over the bullion surface is repeatable when it is constrained in this way. By holding all other variables fixed, such as the friction component, the gravity component, the rod length, the magnet strength, the bullion surface shape, the distance between the magnet and the bullion sample, and constraining the motion of the pendulum in the x-y plane, only two variables are measured, one of which is the angle of motion, and its derivatives, the second is the conductivity of the precious metal. By accurately measuring one of these, i.e. the angle of motion and its derivatives, angular velocity, and angular acceleration, or equivalently the number of oscillations across a complete set of oscillations, one can infer the conductivity of the sample being tested, and match this reading to an authenticated reference sample. This facilitates the gathering of many data readings, that can be compared from one test to another, and that the tests can be compared and stored in a database. A distinct wave signature can be gathered and stored for all items tested real and shown to be a fake, allowing the device to match real wave patterns with previously authenticated wave patterns, but also allowing the device to identify the likely composition of a fake object based on the same database of readings.

Referring now to the figures, where Figure 1 illustrates a general embodiment of a device of the present invention. Specifically, Figure 1 illustrates a perspective view of one embodiment of a device of the present invention and is generally referred to by reference numeral 1 . The device 1 of the illustrated embodiment comprises a housing 50 having at least three walls 52,53,54,55 and a base 56. The base 56 further comprising a platform 4. The platform 4 ensures that the bullion does not move during inspection and analysis. The platform 4 comprises at least one groove that can support a test bullion or a reference bullion and is configured to position the bullion in either a flat or an upright position.

The device 1 comprises a pendulum 11. The pendulum 11 is a rod 12 that is suspended from a pivot point 7 that permits the pendulum to move in an x -y plane of motion, the plane that is facing the smart device or the observer. The friction due to the pivot point 7 is constant. The pivot point 7 is secured to the device 1 via a crossbeam 30. The crossbeam 30 comprises a support structure that spans from the upper portion of one wall 52,53,54,55 of the housing 50 to the upper portion of another (parallel) wall 52,53,54,55 of the housing 50. The crossbeam 30 is typically positioned equidistant between the opposing walls 52,53,54 and is adapted to pivotally hold the pendulum 11 such that the pendulum 11 hangs from the crossbeam 30 and is centrally over the platform 4 the device 1 when at rest.

The device 1 further comprises a release switch 2 for the pendulum 11 . The release switch 2 allows the pendulum 11 to be launched from a resting position to an active (swinging) position. The release switch 2 does not add any additional downward force to the initial launch of the pendulum 11 , thus, preserving the consistency of the initial conditions of the pendulum 11 across devices. The release switch 2 can be positioned on any one of the walls 52,53,54,55.

The pendulum 11 is made up of a rod 12 and a magnet 3. The rod 12 is attached to the pivot point 7 at its distal end 13, while the magnet 3 is attached to or forms an integral part of the pendulum, at its proximal end 14. The magnetic field of the magnet 3 faces downward from the bottom surface of the magnet 3 onto the top of the bullion test sample or reference sample. The magnet 3 never contacts the bullion sample, and the distance between the base of the magnet and the sample is fixed. However, as the magnet 3 traverses across the top face or edge of the bullion sample on the platform 4 (or platform 40 in Figure 2 and Figure 5), the magnet 3 induces a current in the bullion sample, which results in the dampening force on the movement of the pendulum 11 . The magnet 3 can be either removed from the proximal end 14 of the pendulum 11 or left in place, and then covered with a piece of material (so as not to damage the bullion) to strike the bullion as it sits upright in the groove on the platform 4 (or platform 40 in Figure 2 and Figure 5). The purpose of this is to create a sound that can be analysed against the sound of a similar test on an authentic or reference piece of bullion of the same specifications. This sound can be recorded by the smart device, video recorder, or microphone.

In one embodiment, there is an extendable holder 5 that flips out from the base 4 of the device 1 that is configured to hold a smart device 6. The holder 5 positions the smart device to have sufficient distance from the device 1 to capture the full movement of the pendulum 11 . The holder 5 can flip back into the device 1 for storage and transport.

The housing 50 or frame for the device 1 is typically a closed box, the front of the box opens down to rest on a flat surface, the smart device holder 5 attached to the front lid of the box flips out away from the mouth of the device 1 , for the purpose of allowing distance between the inside of the housing 50 containing the pendulum 11 and the platform 4 (or platform 40 in Figure 2 and Figure 5), this allows a clear view of the motion of the pendulum 11 from the camera of the smart device or any recording device, which is used for recording the tests. The pendulum 11 typically hangs in the centre of the device 1 and is composed of the fixed rod 12 and the magnet 3. As stated earlier, the pendulum 11 is fixed such that its movement is fixed in the x-y plane.

The magnet 3 is typically a neodymium magnet of common manufacture but can be made from other magnetic materials; the magnet 3 is cylindrical and encased in a metallic holder. In one embodiment, the exposed face of the magnet 3 is circular. The magnetic field is thus in the downward direction as the pendulum 3 hangs at rest.

The device 1 that contains the pendulum 11 is of fixed width, ensuring that the pendulum 11 is launched in each device 1 at the same angle (the activation angle), and the pendulum 11 is launched using a standard trigger (the switch release 2) from the side of the housing 50. The standard trigger (the switch release 2) ensures that the pendulum 11 is launched with the same initial velocity across devices, and across experiments.

The magnet 3 can be removed from the rod 12 and the rod 12 can be launched to perform a standard knock on the bullion test sample and reference sample positioned in the groove on platform 4 (or platform 40 in Figure 2 and Figure 5). The bullion test sample and reference sample are propped in an upright position in the platform 4 (or platform 40 in Figure 2 and Figure 5) for impact between the rod 12 and the bullion to occur. The groove in the platform 4 (or platform 40 in Figure 2 and Figure 5) supports the upright position of the bullion test sample and reference sample.

Turning now to Figures 2(a), 2(b) and 2(c), there is illustrated one aspect of the claimed invention and is generally referred to by reference numeral 100. Where aspects of the device 1 ,100 are shared, the same reference numerals are used. The device 100 comprises a housing 50 having at least three walls 52,53,54,55, a base 56 and a crossbeam 30 secured to at least three walls 52,53,54,55. The base 56 further comprises a platform 40 configured to accommodate the bullion test and reference sample (separately) when being analysed. A pendulum 11 is pivotally secured to the crossbeam 30, the pendulum 11 comprising a rod 12 having a magnet 3 affixed thereto.

The crossbeam 30 is enveloped by a housing 21 that incorporates a printed circuit board (PCB) that measures parameters from the movement of the pendulum 11 . On top of the housing (50) is a button to turn the device (1 ,100) on, feed power from a battery to the PCB. The housing 21 is bisected by, and in physical communication with, the crossbeam 30. When incorporated into the housing 21 , the PCB is configured to attach to an outer rim of a pair of bearings either side of the crossbeam 30 (typically enclosed within a bearing encasement 207, see Figure 5), which holds the pendulum 11 in position prior to release and during the testing process. The bearings are free to rotate about the crossbeam 30, which permits the PCB to register movement of the pendulum 11.

The PCB incorporates an accelerometer, an accurate closed loop triaxial gyroscope, a triaxial geomagnetic sensor and a microcontroller. This allows the user to measure the motion of the pendulum 11 and transmit the recorded data to a system which analyses the data and provides a reading on the authenticity of the bullion sample being tested, or the reference bullion being characterised.

When the PCB is incorporated into the housing 21 that surrounds the crossbeam 30, as the housing 21 traverses the same angles as the movement of the pendulum 11 when released, the closed loop triaxial gyroscope and accelerometer also traverse these angles. The PCB may also incorporate sensor fusion and measures the orientation of the pendulum 11 in space. As the pendulum 11 moves only in the x-y plane, the radius of rotation (length of the rod) is fixed. The motion can be described by the change in the angular velocity of the pendulum 11 , i.e., measured by the accelerometer only. However, when integrating acceleration to find angular velocity, a drift constant is gained, and when integrating angular velocity to collect orientation or the current angle, another drift constant is gained. A combination of an accelerometer and a gyroscopic sensor is sufficient to gather the motion of the pendulum 11 completely, but in addition to get the absolute orientation, a magnetometer is also used to establish absolute orientation, which means orientation of the sensor with respect to the earth and its magnetic field.

In Figure 3, there is illustrated a trace graph showing the outcome of a test using the device 1 ,100 of the claimed invention. For the test, once the pendulum 11 is released by the release switch 2, which is shown here to be in the wall 54, and the pendulum 11 passes a pre-set trigger angle (the activation angle), the PCB containing the chip, which is equivalent to an inertial measurement unit (IMU), will begin recording and storing data. The pre-set trigger angle, also known as the activation position or angle B (see Figure 5), is an angle programmed in the PCB. The pre-set trigger angle is greater than about 45° and less than about 90° from the vertical axis when released from the right-hand side of the device 1 ,100 (and device 200 in Figure 5) (or 270 “ from the vertical axis if the pendulum is released from the left-hand side of the device 1 ,100). If the pre-set trigger angle is set at, for example, about 55 “ from the vertical, then the IMU may begin transmitting data as the pendulum 11 passes through the 50° angle and is declining in degrees, the IMU will then take and record readings until the oscillations of the pendulum 11 are complete. The IMU will record the angle, the angular velocity, the angular acceleration of the pendulum through one or more accelerometers, the gyroscope, and the magnetometer sensors on the PCB. It is important to note that any one of the above elements on the PCB can be used to measure the motion, for instance an accelerometer on its own will give you the number of oscillations of the pendulum. The IMU will take a reading every 30 ms (or less, it is possible to adjust the PCB to take readings faster or slower than this) and take up to 1000 readings (although this may vary) per test to give an accurate graph (see Figure 3). Once the pendulum 11 has come to rest, all the data points stored in the PCB will be transmitted to an online platform via WiFi® and/or Bluetooth® The calculations to extract the angle of orientation are typically done using quaternions, euler angles, rotation vector, and/or gravity calculations.

Turning to Figure 4 where a sample dimension apparatus 150 is coupled with the device 1 ,100. The sample dimension apparatus 150 comprises a plurality of slots 152 that the most common bullion coins on the market will fit through. The use of the slots 152 as a bullion testing method is another layer of testing that can be used in conjunction with the device 1 ,100 because, for example as gold is so dense it is hard to make a replica that does not have larger dimensions and still has the same weight. The dimensions of the plurality of slots 152 can be used to test over five hundred bullion coins. To determine whether the test bullion coin is authentic, the user simply looks up the type of bullion coin it is in a database, which will then inform the user which slot 152 to insert it through, leading to testing the thickness and diameter of the test bullion coin. The additional advantage of using the sample dimension apparatus 150 is that it will also detect a process known as “shaving of the bullion”. Shaving bullion coins is a technique of doing exactly what it sounds like to cheat someone by depriving them of the stated amount of silver or gold. Precious metal can be physically removed from the coin, which can then be passed on at the original face value, leaving the debaser with a profit. Coin debasement was affected by several methods, including clipping (shaving metal from the coin's circumference) and sweating (shaking the coins in a bag and collecting the dust worn off). This technique can be used for the most popular gold and silver coins on the market.

The slots 152 are cut to match the thickness and diameter of the bullion coins being tested such that these coins can move tightly through the relevant slot. If a fake coin is being tested on the dimension board, one of two outcomes will arise. The fake coin is either too big and will not fit in the slot, indicating the coin is a counterfeit, or the fake coin is too small and does not fit tightly in the slot, indicating the coin is a counterfeit. The latter case arises where a gold bullion coin is an alloy, such as the Krugerrand, American eagle, sovereign, and other such alloyed coins. These alloy coins have a composition of gold and some less dense metal, usually silver and copper. A good counterfeit of these coins will usually use tungsten which has a similar density to gold, thus the counterfeit in these cases can have a smaller dimension to the real coin. This is detected when inserting the coin in the apparatus 150, as the coin does not fit tightly in the slot 152, indicating that the coin should be tested using the device 1 ,100,200 of the claimed invention. In the case of silver coins, as they are less dense, there are more combinations of materials that can be used to try to match the density, this is however still a very effective test on silver coins. Turning now to Figure s, there is illustrated one aspect of the device 1 ,100 of the invention, where the readings captured are generated using a laser beam, and the device is typically generally referred to by reference numeral 200. The device 200, unless otherwise stated, shares the same components as that set out above for the device 1 ,100. The device 200 comprises a bearing encasement 207 for accommodating the bearings on the device 200. There are two bearing encasements 207 on either side of the crossbeam 30, onto which is attached the pendulum 11 . The rod 12 of the pendulum 11 rotates about the crossbeam 30 which is accommodated between the bearing encasements 207. The bearing encasements 207 are held in place by a first support beam 84 and a second support beam 86. The first and second support beams 84,86 further comprise a first foot 87 and second foot 88, which are fixed to the base 56. Figure 5 illustrates the pendulum 11 at the rest position A. When the pendulum 11 is set for release, the pendulum 11 is moved to engage with a stop 80 incorporated on a first stanchion 81 a and is held here at what is referred to as activation position B. The stop 80 forms part of the release switch 2 and creates an activation angle of greater than about 45° and less than about 90° from the vertical axis when released from the right-hand side of the device 200 (or 270 “from the vertical axis if the pendulum is released from the left-hand side of the device 1 ,100,200). The typical activation angle is about 55° relative to the vertical axis (the vertical axis being when the pendulum 11 is at rest position A) when the pendulum 11 is at the activation position B. The stop 80 acts to restrict the motion of the pendulum 11 so that it cannot rise higher than the activation position B. To ensure this, a restraining stop 83 sits proud on a crossbeam 85a, which lies above the stop 80. The crossbeam 85a is substantially parallel to the base 56. To release the pendulum 11 from the activation position B, the stop 80 is pulled away from the crossbeam 85a, releasing the pendulum 11 , which then swings back and forth through the x-y plane generating its oscillations. To prevent the pendulum 11 from oscillating too wildly, an overshoot stud 82 sitting proud on a crossbeam 85b prevents the pendulum 11 swinging beyond this point. The overshoot stud 82 is positioned parallel to the restraining stop 83 and is typically located at the junction where the crossbeam 85b meets a second stanchion 81 b. The crossbeams 85a, 85b are joined to the support beams 84,86, respectively, distal the release switch 2/overshoot stud 82; while the first and second stanchions 81 a, 81 b are also joined to the support beams 84,86, respectively, proximal to the first and second foot (87,88), respectively.

The elements described above can be switched from the first stanchion 81 a/crossbeam 85a to the second stanchion 81 b/crossbeam 85b and function in the same manner as described.

The overshoot stud 82 also offers guidance to the user as to whether the device 200 is on a flat surface suitable for testing, as the pendulum should not hit the overshoot stud 82 if it is released and the device 200 is on a level surface. The device 200 also comprises a laser 210 (which generates a laser beam), which is situated behind the magnet 3 when the pendulum 11 is at the rest position A. When the pendulum 11 is released from the activation position B, the pendulum 11 moves across the face of the laser 210, and the magnet 3 breaks the laser beam. The breaking of the laser beam is recorded by a microprocessor in the base 56, which is in communication with an oscillation counter 90. The oscillation counter 90 is typically accommodated on the base 56, where the user can read the results from the test. The laser 210 can also be aimed at a detector in front of the pendulum 11 . When the pendulum 11 is at rest position A, the connection to the detector and/or the oscillation counter 90 is broken due to the pendulum 11 blocking the laser beam. On each oscillation of the pendulum 11 , and the connection to the detector/oscillation counter 90 is broken, the data is captured by determining how many breaks of the laser beam have occurred during a complete dampened oscillation movement of the pendulum 11 over the bullion and until the pendulum 11 comes to rest. The total number of oscillations of the pendulum 11 over the bullion sample is stored, which is inversely related to the conductivity of the sample. There are two other forces acting on the pendulum during this test.

1 . The force of gravity acting on the pendulum.

2. The coefficient of friction of the pivot and the air resistance acting on the pendulum.

Typically, the device 200 also comprises a PCB, and it does store data, but it does not use a gyroscopic sensor, an accelerometer, or other IMU device. The PCB contains a microcontroller that the oscillation counter 90 runs off. An example of a typical PCB for use would be an Arduino Nano Every, which features a powerful processor, the ATMega4809. All that this PCB needs to do is activate the oscillation counter 90 when the laser beam is broken by the magnet 3. The PCB in device 200 will also do the calibration of the device. Any microcontroller chip would suffice. The printed circuit board in this instance is in the base 56.

A tare button 94 is an optional feature that can be accommodated in the base 56. The tare button 94 is used to calibrate the device 1 ,100,200 before use. A free run of the pendulum 11 in the absence of any bullion will result in a count of higher number than that if bullion was present. This number is then stored in the microcontroller to be used to calibrate the testing run. Pressing the tare button will reset the oscillation counter 90 and store the calibration count number.

The oscillation counter 90 displays the number of oscillations on each run. The displayed number can be referenced against the known result of the standard piece of bullion being tested. This information will be made available on the web platform. To calibrate the device 1 ,100,200 before each sample is tested, the pendulum 11 is fixed at the activation position B, the platform 4,40 is devoid of any reference or test sample, and the pendulum 11 is released by activation of the release switch 2. No electromotive force will be present in this run. A full set of oscillations is recorded to provide an initial calibration count, which is compared against a recommended calibration count in the absence of any bullion. To adjust for any change in the resistance of the movement of the pendulum 11 , or any other factors effecting the forces of gravity or the coefficient of friction, the calibration count is used as a multiplicative factor on the output test result. The output test results will then be as follows:

Output test result = (Calibration Count/ Initial Calibration Count) * The Bullion Test Count

This calibration can be coded into the microprocessor or PCB.

In any one of the above-referenced aspects, the information gathered by the device 1 ,100,200 can be transmitted to the user’s smart device or a central storage system for inclusion to a database, while the device 200 also allows the user to record the results themselves. The latter allows the user to use the device without the need for a network connection.

Materials and Methods

The motion of the pendulum can be measured in various ways, using sensors, for example, an inertial measurement unit (IMU) that can measure a six or nine axis rotation. This can be measured using an accelerometer, an accurate close-loop triaxial gyroscope, a triaxial geomagnetic sensor and a microcontroller all put together in a chip or separately on a printed circuit board (PCB). An example of such is the smart sensor BNOQ55 chip from Bosch® and the MPU-6050 Six-Axis (Gyro + Accelerometer) MEMS MotionTracking™ chip from InvenSense. The sensors can measure the absolute orientation of the pendulum (Euler Vector, 100Hz) through three axis orientation data based on a 360° sphere, or measure the absolute orientation (Quaternion, 100Hz) through a four-point quaternion output for more accurate data manipulation. The sensors can also measure the angular velocity vector (100Hz) through three axis of rotation speed (rad/s) and/or measure the acceleration vector (100Hz) through three axes of acceleration (gravity AND linear motion) in m/s ^A 2. The sensors can also measure the magnetic field strength vector (20Hz) using three axis of magnetic field sensing in micro-Tesla (uT). This will give up to 1000 readings per second, to give the exact motion of the pendulum over the bullion.

Another method that can be used to measure the movement of the pendulum is the use of a rotary encode, which will measure the motion in relative terms. The use of a hall effect detector at the base of the device. This would involve building a linear sensor into the base of the device and using this to track the motion of the pendulum by measuring the change in magnetic flux across the base of the device over time.

Another method that can be used to measure the number of oscillations of the pendulum is the use of a photoelectric sensor, such as a thru beam sensor, retro reflective sensor or a diffuse reflective sensor. In each case the photoelectric sensor beam will be interrupted as the pendulum traverses its path, counting the number of oscillations of the pendulum, which in turn will be proportional to the conductivity of the precious metal being tested.

The device 100,200 typically runs on a battery, and preferably a rechargeable battery. However, the device 100,200 can also be connected to a mains voltage supply, typically supplied as an alternating current (A.C.). The device 1 can be operated manually, without a power supply, or with a power supply as set out for device 100,200.

Overview of the

Step 1 : The sensitive scale of standard manufacture is calibrated using a standard weight, usually 50g. The Bullion is weighed using the sensitive scale. If the Bullion is still in its packaging it may still be weighed, and the weight compared to an authentic counterpart (reference sample) also in its packaging.

Step 2: The bullion is placed in the indentation or groove in the platform 4 and the rod 12 of the pendulum 11 having the magnet 3 removed and a hard protective covering (sheath) placed over the end of the rod 12, the rod 12 is released to strike the bullion creating a resonance sound. The sound is recorded and measured. The magnet 3 typically clips off and the hard protective covering will not damage the bullion on impact. As the rod 12 will fall at the same speed every time when released from the release switch 2, this will provide an impact on the bullion that is the same every time, thus creating a sound that can be compared to a sound generated previously on a reference sample. An acoustic sensor in the PCB can be used to record the sound of the knock.

Step 3: The magnet 3 is placed back on the rod 12; the bullion is placed on the platform 4. The platform 4 is placed directly underneath the pendulum 11 , the centre of the bullion is aligned with the centre of the magnet 3.

Step 4: The pendulum 11 is released, and the oscillations, amplitudes and periodicity, angular acceleration, angular velocity, orientation and absolute orientation of the pendulum motion are all captured and recorded using a smart device or the PCB incorporating an accelerometer, an accurate close-loop triaxial gyroscope, a triaxial geomagnetic sensor and a microcontroller, or by recording the number of times the pendulum 11 breaks the beam generated by the laser 210 that is in communication with the microprocessor. The physics for capturing the weight, and the volume of the bullion are transparent. The knock creates a standard sound as it hits against the bullion. This sound can be compared with authenticated bullion when it is knocked using the same procedure in the same device.

The solutions to the equations of motion for this pendulum physical set up are non-trivial but solvable. However, the equations can be set up with reasonable ease.

By Newton’s formulas the overall force on the system is equal to the sum of the forces, (or equivalently the sum of the torques is equal to the overall torque). Giving a second order differential equation. The individual forces are as follows:

(i) The gravitational force acting on the pendulum.

(ii) The dampening “drag force” due to air resistance and the friction from the pivot of the pendulum.

(iii) The electromotive force (EMF), due to the presence of the bullion and acting on the motion of the pendulum in the opposite direction of the pendulums motion.

The EMF is dependent on, for example, the distance between the magnet and the bullion at any time t. Thus, this force can be increased or decreased by changing the distance between the surface of the bullion and the magnet in motion. For example, one can increase or decrease the length of the rod suspending the magnet, or by increasing or decreasing the thickness of the platform 4 which is accommodating the bullion being tested.

Thus, the force can be increased or decreased by changing the magnet type or distance between the magnet and the bullion being tested, and hence the magnetic field strength of the magnet.

The force induced depends on the shape and volume of the bullion undergoing the test. As bullion coins and bars come in standard shapes and volumes, this allows the user to accurately compare one bar/coin to another bar/coin.

The device of the claimed invention is set up to take a reading from a piece of bullion and compare the results with a previously stored data set resulting from a test of bullion of the same shape and volume and dimensions as specified by the bullion manufacturer. Each additional set of results is added to the database of results to give a larger data set of results for comparison to new tests. A statistical probability of authenticity can then be provided to the user based of this data.

The conductivity of the bullion: most importantly as the above measures (dimensions of bullion, rod length, magnetic field, angle of pendulum launch, and other variables in the equations of motion) is fixed in any one experiment, the variable that affects the motion of the pendulum, is the conductivity of the bullion. The conductivity is proportional to the EMF being induced on the pendant and is the factor that is compared when we compare across experiments.

By solving the equations of motion, the pendulum’s position at any time t, can be extrapolated, as well as its periodicity and the number of oscillations expected for a particular piece of bullion, these results can also be used for a sense check of the observational results.

Results can be captured from the experiment in a number of ways, the most basic being an observation by the user, where the user simply counts the number of oscillations, this is challenging as the oscillations are rapid but can be done. The device 1 ,100 itself is designed, in one aspect, to have a mounted smartphone in the holder 5 so that the results of the experiment can be recorded and analysed accurately.

In the specification the terms "comprise, comprises, comprised and comprising" or any variation thereof and the terms “include, includes, included and including" or any variation thereof are considered to be totally interchangeable and they should all be afforded the widest possible interpretation and vice versa.

The invention is not limited to the embodiments hereinbefore described but may be varied in both construction and detail.