Chrome plated zinc or stainless steel?

A real quick look at the difference between chrome plated zinc and stainless steel boat hardware. When to use and more importantly when not to use.
Thanks for watching.
You can buy all your boat hardware at canadawidemari...

[@peace4world]

Is there a quick non-destructive test that one can do on a part to determine if it is chrome-plated zinc or stainless? Thanks for your help.

[@peace4world]

... And both are non-magnetic.

[@CanadaWideMarine]

Weight is the first clue, stainless steel is much heavier than the zinc. Stainless steel also has a darker color to it, even when highly polished, than the chrome.
Chrome plated zinc parts are generally cast parts, and the backside of them is of a poor quality finish whereas stainless steel is often forged, but even the cast stainless steel has a better quality finish on the backside. The backside is not usually polished on stainless steel, whereas chrome plated zinc is fully chromed. And price. Chrome plated Zinc is much cheaper than polished stainless steel.
If you are trying to identify older parts already installed on the boat, look for signs of pitting or bubbling or any other imperfections of the chrome plating, the stainless steel products do not have those troubles.
I hope that helps, it's not really a "test" more just general experience. Once you see a few pieces side by side a coupe times you will be able to identify the difference pretty quickly.

[@peace4world]

​@@CanadaWideMarine Densities listed on Google for stainless steel is ~8 g/cc and diecast zinc about 6 g/cc, so you are very correct! I recently bought a garlic press from Amazon (shorturl.at/dkDMR) and wanted to see if the stainless claim there is false (which is likely since such a complex shape can be difficult to make out of SS). So, a weight comparison without a second unit made from a known metal would be difficult. Density calculation using water displacement is also not so easy.
But your second point is superb! The inside of this device is shiny but slightly yellowed and duller (not bright luster as the outside). So, one conclusion could be that it is not chrome plated since that would show on the bottom equally well. But the other thing is why is SS somewhat pale yellowish on the bottom!
Thank you for your time and guidance. It has increased my knowledge.