Metal Ware

How can you tell that an item is made of brass?

I bought a small ornament from a shop in Marrakech. The owner told me that it was definately made from Brass. Th item is very heavy…only small in size…8 inches tall by 5 inches wide….but is quite dense….how can i prove that it is or is not Brass?

Brass is gold colored, when clean, and fairly heavy. The first test of something being brass is to make sure it looks and feels like brass. There really are not too many options for things that look and feel like brass. Assuming it does, your basic options are it is brass, copper, bronze, gold or brass-coated steel. Bronze and Copper are both darker and less yellow so you may be able to rule these out visibly.

You can rule out the brass-coated steel with a magnet. A magnet will not stick to solid brass but will stick to coated steel.

Brass is an alloy of copper and zinc and can vary from as much as 95% copper to as little as 50% copper. The less copper, the lighter the coloring and the harder the brass.

If you could chip off a flake of the ‘brass’ to test, nitric acid will make it give off a greenish color, due to the copper content. Copper and bronze will do the same. Gold will be unaffected. I suspect we can rule out gold anyway.

If you really want to be sure, an electronmicroscope is another means of identification, but not one that’s easy for the layman! The spectralanalysis would give you an indication of the metals in the alloy.