[shane12345]

Hi all!
I am trying to recreate a blue patina on hot dipped zinc galvanized steel often seen on well worn handrails where hands have been rubbing.
No amount of polishing will work, the zinc stays bright silver right thru until it is polished thru to the steel underneath. I am convinced it is a chemical reaction with something on our hands and possibly water.  I've tried polishing with boiling water/steam, vinegar and salt all unsuccessful.
Would anyone know what reaction might be taking the silver effect out of the zinc leaving the blue/grey color behind?
See link below to an example of the effect that I am trying to recreate.
Thanks in advance. 
https://postimg.cc/dkDg72vj