Hi Stathi,
       In the Borough of Queens, where I live, and in parts of Brooklyn, the
trolleys ran on overhead wires. In fact, trolleys were replaced by electric
buses and these buses ran on overhead wires too. As children, we had fun
watching the bus poles "spark" on the wires.
       The trolley tracks supposedly contained nickel, titanium and some
other metals. I realize nickel hints of stainless steel but I doubt if that
was the case. NYC trolley tracks were/are worth a LOT of money in scrap
because of these metals - some individuals actually went digging them us,
along with the "Belgian Blocks" as the granite cobble stones were called,
until the police moved in...
       I believe the early tracks were made from "puddlers" iron/steel, the
Bessemer process came later.
Russell Rudzwick