We still use glass block in those places. But today they are used almost everywhere else, too.
Glass is one of the oldest and most useful products we have. It dates back to about 4000 B.C.
In ancient times, formed pieces of colored glass were thought of as precious stone.
Because the center of glass block is hollow, it provides dead air space, which is good for insulation. The shape of the glass diverts and distributes the light coming through it in odd patterns, giving the deflected light an added decorative effect in the room.
Some blocks are clear, while others are more obscure, allowing the light coming through to vary according to the style of block.
Typical 4-inch-square blocks can be used in countless ways.
The blocks, which also come in larger sizes, can be placed in a stepped-up or stepped-down pattern. They can be set straight with an opening in the middle or off to the side. They can be positioned in various geometric shapes. And the list goes on.