If I wanted to find out what kind of metal some lures/blades/tackle is made out of (or plated or finished with), how would I go about doing that?

Any recommendations for someone in the Seattle area who could definitively tell me whether something is nickel, brass, gold, silver, etc?

Since its plated and not solid, you'd need a Mass Spectrometry Analysis performed. If it were solid, we could solve it ourselves with a glass of water and a calculator.

Spec testing generally requires many dollars, but here's a couple of local labs anyway...

http://www.intertek.com/analytical-laboratories/mass-spectrometry/

https://www.engsys.com/contact-us/washington

You could contact a NDT (Non-destructive testing) shop. PMI (positive material identification) is pretty common for welding and receipt inspection. I imagine it could be used on the materials you mentioned.

I see Nick already listed intertek. Here's some of their discussion: http://www.intertek.com/non-destructive-...tification-pmi/

Thanks!