The 6" stainless steel post is not a support but a wiring chase bringing electrical wires from the ceiling into the island, which means we were able to put it in during the cabinet installation, and work in a sequence convenient for the cabinetmaker....
working around a support post is a little bit more complicated....

I have a supporting post in my kitchen. I like what you did with the steel poles. What material did you use to do this?

this is not a support post, but a chase for electrical wiring. if you have a post it's either steel of a few pieces of 2x4 or 2x6 bunched together...? if you need to cladsuch a post you can do this with a number of means, depending on your personal style/taste/budget....some of my work has posts wrapped in cabinet material and some sit invisible inside tall cabinetry. if you want to wrap it in stainless steel as on the photo then you need to contact a metal shop to see what they can do - essentally it's a sleeve around the post, so there might be need for a seam.