Crackle glass was invented in the 16th century by the
master glassblowers of Venice. The crackle effect is
produced by submerging molten hot balls of glass in very
cold water. This resulted in the outer layer of the glass
cracking. The process would then continue with the glass
being reheated and blown into the desired shape. As the
glass was shaped and expanded, the cracks would become
larger, resulting in a distinctive crackled effect.
Crackle glass (often spelled "craquelle") did not
become popular until the late 1800s. It was made
in many factories in the United States and Europe.