The phrase "glass bricks" refers to building blocks that are made of glass instead of traditional material like clay or concrete. They are transparent or translucent, allowing light to pass through. Full definition
On the far side of this great room is a unique curved glass brick wall, on the other side of which is the gourmet kitchen that is decked out with an espresso machine and ice cream maker among other major appliances. (luxuryretreats.com)