I've been using Beadalon 49-strand silver-plated wire for floating necklaces. Will the wire will tarnish over time like silver jewellery?

Since all Beadalon wires are nylon-coated, they resist tarnishing. I make the same type of necklaces you're describing and haven't had any problems with tarnish. As the Product Manager, says, "The nylon coating does give some tarnish resistance, but as with anything made of or plated silver, as the sulphur dioxide penetrates the coating it will cause tarnish at some point.

It’s difficult to say just how long because of all the external stuff going on in our atmosphere and inside our homes/factories/warehouses etc. more.

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