Weight and Purity of Non-Ferrous Metals Based on Density; Calculation Without a Laboratory

In non-ferrous metals, density is not merely a physical number; it is a working tool. With this single number, you can both estimate the weight of a piece before weighing it and, without any laboratory, make an initial assessment of whether the metal in front of you is really what it claims to be or not.

Density Table of Non-Ferrous Metals

Every metal has its own specific density, and this difference is the key. The table below shows the density of common non-ferrous metals on the market; memorize these figures, because they will come in handy many times.

With a density of ۲.۷, aluminum weighs about one-third as much as copper; this lightness is both an advantage and a distinguishing characteristic.

How to Estimate Purity Without a Laboratory

The simple method is to take a piece with a measurable volume, weigh it, and divide the weight by the volume to obtain the actual density. If the figure is close to the reference density of that metal, the purity is acceptable; if it is noticeably lower or higher, there may be impurities, an inferior alloy, or a different metal. This method does not replace precise laboratory analysis, but for a trader at the point of transaction, it is the fastest possible assessment.

This same simple relationship between weight and volume is the difference between someone who buys blindly and someone who knows exactly what they are buying.

A Practical Point About Alloys

Alloys such as brass have a density range rather than a fixed number because their exact composition varies. If the obtained figure falls within this range, do not worry; however, if it is completely outside the stated range, the alloy’s composition may differ from what has been claimed, or another metal may have been mixed with it. For major alloy transactions, it is better to accompany this estimate with an additional test.