I don't know what "blue" brick are.
The most interesting brick I've seen locally are in a building in Baltimore called the Commerce Building. As far as I can tell, the bricks they used are "double-fired", being made normally, and exposed to a sand or ceramic coating that is then sent back into the kiln to produce a smooth ceramic surface on the brick, even before it is assembled into walls.
They even have bull-nose bricks for the corner. It's a lot of effort and a very nice, and very permanent, effect.
That building also has a mural dedicated to modern transportation around the upper portion of one well-illuminated room. Featured on that mural is a distinguished looking four-funnel steamship recognizable to most. Yes, lads and ladies, a painting of the Titanic graces a mural in Baltimore!
You've got to keep your eyes open around this town!
Maybe he means brick painted blue.
Afternoon All.
Blue Brick:
https://www.ketley-brick.co.uk/staffordshire_blue1.html
If you hit a normal brick with a hammer and bolster ,the brick breaks in half.
If you hit one of these with a hammer and bolster, the bolster bounces off. You have to really want to break that brick in half.
The building is made from them due to being built on very mobile clay. They can cope with significant flexing from the concrete raft.
They aren’t always Blue in colour, the term refers to the common name of Engineering Blue Brick.