Borosilicate glass is the most popular material for bongs thanks to its durability and heat resistance. You can drop some of the best borosilicate glass bongs from a great height and they'll not break.
The one you want to look for is borosilicate glass, also known as scientific glass. Borosilicate glass is used in research and medical settings. As you can imagine, medical-grade glass is perfect for bongs, too.
