How do I definitively check for silver plating on my clarinet?

Qusetions: I possess a D Noblet Paris clarinet (Grenadilla wood, and built from the 40's, and when polished a pitch black residue arrives off, and it tarnishes rather quickly) and ahead of i phone up the man i purchased it from or shell out income getting nitric acid, i wondered if there have been any "home remedies" for testing for silver plating, i've my outdated pupil clarinet which i do know has nickel keys to check in opposition to. (i currently know with regards to the match check and mustard check..any other folks?) many thanks!

Answers:Take it to a jewellery retailer plus they will inform you.