marble chips/stones to cover Resin bottom rail and feet/bottom plate

[kidspoolmom]

My bottom plates/feet are resin and did not come with covers. Sadly based on all the pics, I assumed, the covers came with the pool. We have purchased marble chips/stones to surround and cover the perimeter. I want to get some input on the best material to prevent any reaction with the pool wall and bottom plates and rail. If the marble chips/stones are good than I am good to start building the deck...woot woot! I would just like some additional opinions.

Thank you!