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BullionStar Guarantees the Authenticity of All Bullion Products

BullionStar guarantees the authenticity of all items sold.

Most of our products are procured directly from world renowned mints and refiners with whom we have primary dealer contracts, meaning that the bullion products are shipped to us directly from the production line. 

BullionStar only works with well-known, trusted suppliers and manufacturers of bullion. For orders from such suppliers, BullionStar unpacks the items under camera surveillance and conducts sample testing as described below.

These mints and refineries have extremely tight standards and error margins to meet the requirements set by the London Bullion Market Association (LBMA). As such, BullionStar’s testing is a second and complementary test in addition to that which has already been conducted by our precious metals suppliers.

Precious metals manufacturers certify the authenticity of their products with assay marks and stamps. This constitutes the manufacturers' guarantee of purity and weight for their products. Furthermore, we also guarantee the authenticity of all items purchased from BullionStar.

BullionStar tests the authenticity of its products through density testing, ultrasonic thickness testing, resistivity testing and x-ray fluorescence (XRF) testing.

See the list below with links to some of the renowned mints and refiners whose products we proudly offer:

Heraeus Precious Metals GmbH & Co. KG

PAMP - Produits Artistiques Métaux Précieux

Royal Canadian Mint

The Perth Mint Australia

The United States Mint

In the case where a bullion item does not originate directly from a precious metals mint or refiner, we always test the item thoroughly before reselling it using different testing methods, as described below, to ensure the authenticity of the bullion. 

Density Testing

BullionStar records, in its administration system, information about the dimensions and weights of different types of investment precious metals items. As every metal has a unique density, it is difficult to replicate the density of a precious metal with an alloy of other metals exactly while retaining the dimensions of the product. We therefore check the dimension and weight for items received. We check the weight by weighing the item on a Singapore government agency approved and calibrated precision scale detailing the exact weight down to 0.01 gram. The scale model used is PGW4502e which is approved by the Singapore government agency SPRING. The dimension is checked by using a precision caliper that checks the diameter, length, width and thickness down to 0.01 mm. 

Ultrasonic Thickness Testing

Density testing, as detailed above, detects most irregularities but is not 100 % fool-proof. Density testing will normally detect all replicas except for tungsten replicas of gold. This is why BullionStar also uses ultrasonic thickness testing with an ultrasonic thickness gauge produced by Kern & Sohn GmbH.  

Ultrasonic thickness testing measures the thickness of a metal based on the time it takes for the ultrasound to travel through and return to the surface of the bullion. As the speed of sound for gold is 3240 meters per second and the speed of sound for tungsten is 5174 meters per second, the difference is significant and a gold bar replica produced in tungsten can easily be detected.

When measuring the thickness of, for example, a gold bar, after calibrating and setting the speed of sound for gold on the ultrasonic thickness gauge, the actual thickness of the gold bar must match the reading of the thickness reading on the ultrasonic thickness gauge. If the reading on the ultrasonic thickness gauge deviates significantly on a bar that has passed the density test, it raises reasons for suspicion and further testing will be performed. 

Resistivity Testing

The Precious Metal Verifier by Sigma Metalytics is used to measure the bulk metal in a bullion bar or coin and ensure that the metal matches the electrical characteristics that would be expected of it. The Verifier can assess a sample in less than one second without affecting the coin or bullion in any way. No chemicals are used and no physical damage is done to the coin or bullion being tested. Plating and surface features do not significantly impact the unit's ability to measure the underlying metal. The Verifier uses electromagnetic waves that penetrate deeply into the coin or bar, while plating and surface features are largely ignored, and thus the main body of metal is assessed. The Verifier can see through plastic cases and bags, therefore numismatic coins do not need to be removed from protective holders. Different sized sensors are used for different sized samples.

The user selects the metal that the sample is purporting to be. The Verifier sets the value of that metal’s resistivity to the center of the bar display. The bar display has brackets that show the expected range of the reading for the selected metal. So, for example, if the user selects pure gold as the metal, and pure gold is placed on the sensor, a value within the brackets will be obtained. Any other metal with a similar weight will fall far outside this range. If the actual reading does not correspond to the expected reading, an arrow will show up on the bar display. Many standard metals are stored in the Precious Metal Verifier and can be selected by the user. For example, for gold coins, the user can select pure gold, 22 K gold or 90 % gold. For silver, the user can e.g. select pure silver, sterling silver or 90% silver. Pure platinum, palladium, rhodium, and copper also have stored values. Each of these coin and bullion metals will produce a unique reading on the Precious Metal Verifier.

X-Ray Fluorescence (XRF) Testing

BullionStar also tests purity and composition of samples with its Olympus Portable Countertop GoldXpert XRF Analyzer.  

XRF is a proven method of chemistry analysis and determination of purity and fineness of precious metals. XRF analysis is a non-destructive multi-elemental testing alternative to assay metals. The GoldXpert XRF provides a reading of the alloy chemistry and karat classification of the metal tested. It furthermore assists in identifying gold-plated objects by alerting the user on the screen of the analyzer. The GoldXpert XRF is easy to use as it provides karat and compositional analysis results with one push of a button. 

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