Is there any reliable way to tell if an article (such as a bell) is made of brass or bronze, without the use of specialised lab facilities? The issue is important for the many thousands of collectables and antiquities on the market, since bronze is much more expensive.
As I understand it, the brasses and bronzes in common use fall into quite separate groups (high-zinc vs high-tin), apart from a few misnamed alloys. One would think it would be easy to distinguish them, but to do it without lab test equipment and without damaging a collectable item is harder.
Colour: Useless. Certain bronzes have the same colour as brass, and the colour of the patina on ageing is not reliable.
Hardness: Bronzes, espec. high-tin bronzes, are much harder than brass, but it is not easy to estimate hardness informally.
Sound: High-tin bronzes make bells with a much better sound than brass, but it requires a bell expert to be sure, & it doesn't apply to other items.
Chemistry: Is there a test which is simple enough to use as "kitchen chemistry" and sensitive enough to use when one can't cut or file off a sample?
Any other ideas? Thanks
ross
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