Material used on hands and markers of IWC Portuguese

Hi IWC lover !!,

I'm about to own my first IWC: Yacht Club Black Dial next week.
One curious that I have been digging thru internet for a while but cannot search for the answers.

For standard portuguese Yacht Club and Classic (Steel Case)
what are materials that made for Hands and Markers , what are those silver things made of ?

thanks for comment and answer in advance.

I don't know, but would image plated brass!