Detecting Genuine Copper and Aluminum from Counterfeits; A Magnet and Scale, Two Simple Tools

You buy a spool of copper wire that looks completely copper, but its weight is slightly lower than expected. You bring a small magnet close to it and see that it is attracted. At that moment, you realize that this is not pure copper; it has an iron core covered with only a thin layer of copper. In non-ferrous metals, these two simple tests can prevent the biggest losses.

Why Non-Ferrous Metals Differ from Steel

In steel products, fraud usually involves reducing dimensions and weight. In non-ferrous metals, because the value per kilogram is much higher, the incentive for fraud is also greater, and the common form is to make a cheaper metal (usually iron or an inferior alloy) look like a more expensive metal by applying a layer of copper or paint. Fortunately, the physical properties of these metals themselves provide you with the tools for identification.

Pure copper is non-magnetic and has a high density; these two properties are the simplest tools for distinguishing genuine products from counterfeits.

Two Key Tests Every Trader Should Know

A Common Trap in Wire and Cable

A common trick in wire and cable is making the insulation excessively thick compared with the conductor so that the actual volume of copper appears not to be lower. If the coating thickness is unusually high relative to the copper conductor, there may be a possibility that the copper weight has been reduced and compensated for with insulation. Cutting a sample and observing the actual conductor diameter reveals this fraud.

A few seconds of working with a magnet and a scale, for a product that costs several times more per kilogram than steel, is the cheapest insurance against a major loss.