The phrase "a railing of" is correct and usable in written English.
It can be used to describe a railing that is part of a structure, such as a balcony, staircase, or deck.
Example: "The house featured a beautiful wooden railing of intricate design along the staircase."
Alternatives: "a railing made of" or "a railing constructed from".
Bound by a railing of thick safety glass, the mezzanine is reached by a steel and oak staircase near the arched doorway overlooking the canal.
At its center, three video screens form an enclosure, which the viewer is kept from entering by a railing of suspended aluminum bars.
With a column at left that's almost 12 feet tall, an arch-shaped slab above inwardly angled walls and a railing of thin rods across the front, it resembles an oversize model for a Postmodern hotel balcony.
For editing and rereading, she likes a rocker on the large back porch, which has a slot pine ceiling painted sky blue and a railing of carved cedar posts.
I sat on a railing of bricks and found that when I fell off on purpose everyone laughed, including my grandmother, who made it her job to scare the shit out of people. . . .
I don't understand why anyone would stand on a railing of a tiger enclosure and shout.
The car came to rest, pinning a man against a railing on the steps of State Supreme Court.
A chilly wind blew as the four band members positioned themselves — symmetrically — by a railing on the roof of the MetLife Building, atop Grand Central Station.
The mayor survived the tsunami by clinging to a railing on the roof of the city hall as the waves crashed over him.
But you were reluctant to place your hand on a railing for fear of getting smudged with wet varnish.
Dzhokhar laid his down in front of a store and near children who had climbed on a railing for a better view of the race.
