the cap is stainless steel not chrome, just sayin (no chrome)
Some (not all) Gorilla replacement lug nuts are chrome plated.
Gorilla also sells stainless steel capped lug nuts (over hardened steel) just like OEM.
In "chrome plating" ... typically there is a 45 micron nickel layer electrodeposited and then a 3 micron layer of chromium over that. In some cases there is a layer of copper electroplated first, before the nickel. That layer can be buffed to a high shine. On chrome plated lugs nuts, after a time you will observe the chromium layer chipping off in spots and then surface layer corrosion begins to form.
https://themotorhood.com/themotorhood/2015/7/28/the-shining-chrome-plating-explained