Gate 3: Metal and Measure

Why the Metal Is the Fraudster’s Last Stand

By the time a deal reaches Gate 3, the fraudster has already invested significant effort. They have forged the origin documents. They have crafted a convincing contract. They have built a relationship with the buyer. The metal is the final piece of the puzzle. If the metal passes inspection, the money is released and the fraud is complete.

This is why fraudsters are so creative when it comes to faking gold. They plate tungsten bars with gold. They insert tungsten rods into hollowed-out gold bars. They salt samples with high-grade gold dust to fool assayers. They bribe assayers to report false results.

The Anatomy of Fake Gold

The most common method is to take a base metal — usually tungsten or lead — and plate it with a thin layer of gold. Tungsten is a popular choice because it has a similar density to gold. A tungsten bar will weigh approximately the same as a gold bar of the same dimensions. Without a proper assay, it can be almost impossible to detect.

Another technique is the hollow bar. The fraudster drills out a cavity in a genuine gold bar, inserts a tungsten or lead core and then seals the hole with gold. Only a destructive assay will reveal the deception.

A third method is the salted sample. The fraudster provides a sample of gold that is genuine, but the bulk shipment is fake. This is why sampling protocols are so critical.

The Fire Assay: The Gold Standard of Testing

The fire assay is the oldest and most reliable method for determining the purity of gold. The process involves melting a sample of the gold, adding lead and other fluxes, and heating it in a cupel. During the heating process, the lead oxidises and is absorbed into the cupel, taking any impurities with it. The gold remains behind as a small bead that is weighed and analysed.

Fraudsters hate the fire assay for a simple reason: it is almost impossible to fake. If the seller refuses to allow a fire assay, or insists on using a less reliable method like X-ray fluorescence, you should be deeply suspicious.

Step-by-Step Metal Verification

• Step 1: Visual inspection. Examine every bar for signs of tampering.
• Step 2: Weight verification. Weigh every bar on a calibrated scale.
• Step 3: Dimensional verification. Measure the length, width and height of each bar.
• Step 4: Non-destructive testing. Use X-ray fluorescence to test the surface of the bar.
• Step 5: Destructive testing. Drill or cut a sample from the centre of the bar for fire assay.
• Step 6: Parallel assay. Send the sample to two independent assayers. Compare the results.

Red Flags Specific to Gate 3

• Seller resists destructive testing. A genuine seller has nothing to hide.
• Assayer chosen by the seller. If the seller insists on using a specific assayer you have not vetted, assume the assayer is compromised.
• Inconsistent serial numbers. The serial numbers on the bars should correspond to the refiner’s records.
• Seller offers a discount for cash. This is a classic money laundering red flag.

Real-World Case Study: The Tungsten Gold Scandal

I once encountered a shipment where bars had been hollowed out and filled with tungsten, then plated with gold. The markings were correct. The weight was within tolerance. The surface X-ray test showed gold. The seller resisted a fire assay. I refused to proceed without one. The fire assay revealed tungsten. The buyer’s money was safe. That case reinforced my belief in the importance of destructive testing.

Remember my golden rule. Pass all four gates and the deal is clean. Fail any one and you are dealing with a crook. No exceptions.