What is a glass block made from?

A glass block is primarily constructed from two pieces of patterned glass that are fused together, creating a hollow structure. This design not only provides the desired transparency but also allows for insulation and light diffusion, making glass blocks popular in architectural applications. Their hollow nature contributes to their lightweight characteristics compared to solid glass, and they can effectively retain heat while still letting natural light into spaces, enhancing both aesthetics and energy efficiency in buildings. The use of two fused pieces also enables creative decorative patterns, adding to their appeal in design contexts.