Limited quantity, once these are sold there are no more.
Very small. Buy a few.
How does this compare with our other (most powerful, Neodymium) magnets?
Uses for testing
Gold and silver are not magnetic. So when you are presented with dozens of items to test, save time by picking out all the items that are magnetic.
This does NOT mean that there are special magnets for testing gold and silver. If an item is NOT magnetic, it could be any one of hundreds of metals (including gold and silver).
Silver is strongly 'diamagnetic'. If you slide an appropriate magnet down a flat silver surface (e.g. a coin) it will move slowly instead of 'falling off'. Copper is slightly diamagnetic. See our 'magnets for silver testing' - a set of 3 magnet, a sample copper coin and instructions.
Copper is not magnetic, neither is brass (a mixture of copper and zinc) or bronze (a mixture of copper and mostly tin). A magnet is useful because many copper / bronze / brass items are really steel that has been plated and will (in most cases) be very magnetic. As with gold and silver: if an item is magnetic it is not solid copper / bronze / brass.
Not sure which magnet to buy? We have a bargain sample pack of nine different magnets (both iron and neodymium), click here.