Originally Posted by JillyIsJustKidding
I don't think I've ever seen a hookah with a glass stem. The reason probably is that if there was a glass stem, it would crack from the heat
glass can usually stand very hot temperatures. what causes glass to crack is a rapid change in temps..
however, pyrex is used in a lot of labs and cookware because it's designed to be more resilient to cracking. There's a mr. wizard demo of him putting a normal glass bowl and a pyrex glass bowl on a block of dry ice. he then pours in molten lead and the pyrex bowl holds up while the normal glass bowl cracks, causing the lead to hit the dry ice and smoke everywhere!