any low-cost or no-cost procedure for testing if a conductor is copper or silver.
Some people claim to hear a difference - perhaps someone could listen to them and tell you? - that would cost nothing ;-)
Autosports - the best copper I know of is zero crystal 9N copper that is 99.9999999% pure or 7N silver that is 99.99999% pure.
Kenobi -testing for purity is very easy - just weight your banana plug (just the metal part) and then drop into water to calculate volume. Once you get density you know what it is. If banana plug won't give you accurate reading of displaced water - then use 1000 of them. I hope it was helpful.
One of my friends is working at the pawn shop and he had a customer who brought him a gold slab to sell. A monetary standard gold slab should weigh about 50 kilos and eventually it did, but he decided to drill a hole... After just less than millimeter of drilling the tin started to come up above the drill bit... What d'u think?
1.)Get a bowl large enough for submerging a piece of each. Place each sample in the bowl.
2.) Pour vinegar(any kind) into the bowl.
3.) Wait three minutes.
4.) If one of the sample turns greenish, that's copper. If one turns whitish, that's silver.
5.) If both of them turns whitish or greenish, or no change in color at all, then, the vinegar is fake!
Why don't you scrape an inner surface where it will not be visible (if it bother's you) and examine the shavings with a magnifying glass and the mark you made. Silver should not have any other color present except silver of course unlike copper shavings where it should be obvious with a magnifying glass. Just a suggestion only of course.
In order to do the Density / Displacement test you need several things.....usually inaccessible to most persons.
1. Source of REALLY pure water. Distilled is best.
2. Temperature control. Everything should be at same temp.
3. Metler Balance or equivilent....a scale which goes to 5 or 6 significant digits.
4. A way to meaure extremely small volumes of water. 3 or 4 millilitres ought to do it.