Construction materials named after a capital?

Looking for construction materials named after a capital city for your crossword puzzle challenge? This exciting clue will test your knowledge of both building supplies and global geography. Get ready to put your thinking cap on and solve this intriguing crossword clue that will have you thinking outside the box. Stay tuned to learn more about this interesting connection between construction materials and a capital city.
Construction materials named after a capital?

Available Answers:

I-BEAMS.

Last seen on the crossword puzzle: NY Times Crossword 17 Feb 24, Saturday