Bowls & Ground-Glass Joints

January 5, 2021

Bong Bowls


A “bowl” in the marijuana world refers to the hollowed out glass dish which holds the ground-up marijuana in place before it is lit and smoked.  Depending on the usage, bowls mostly come in either glass or metal.  With pipes, a bowl can be built-in, detachable with a frosted male/female ground-glass joint, or, as is the case with some metal pipes, can screw on and off.  But with Bongs, the bowl is almost always detachable with a tapered male/female ground-glass joint.  


What do you mean by “Glass Joint” when referring to Bongs and Rigs?


The word “joint” can confuse people when used in reference to marijuana and cannabis, because they immediately think of a marijuana cigarette.  However, when we use the term “glass joint” we are referring to something quite different.  We are actually referring to the connecting male and female pieces between two different glass marijuana objects, such as a downstem and a bong, or an adaptor and a bowl or a domeless nail and an oilrig.  “Joint” in this case means the actual joining pieces of glass, both separate and together.  


There are 6 main sizes of glass joints.  These have become the standard:


  • 10mm Male
  • 14mm Male
  • 19mm Male
  • 10mm Female
  • 14mm Female
  • 19mm Female



Every bong has some kind of bowl, and the bowls are usually made with a male ground-glass joint, which fits snugly into a female ground-glass joint on either a stemless bong or on a downstem inserted into a bong.   They are conically tapered and slide easily in and out of one another.  There are three standard sizes of glass joint: 10mm, 14mm and 19mm, with 14mm being the most common.  They are usually frosted, or use “ground-glass”, which is a secure connection method taken directly from the scientific glass community. The joints have been used for years in laboratories to quickly, efficiently and easily fit leak-tight apparatus’ together.  Since most of the borosilicate glass in the bong and oilrig community is based on scientific glass, this makes perfect sense, and follows the tradition of relying on a model of high-standard craftsmanship to create glass devices for smoking, vaping and dabbing cannabis.  


Glass Bowls, just like their bong and oil rig counterparts, come in a variety of styles.  


Scientific glass bowls are usually as deep as possible to allow more ground up marijuana to fit inside and their height and width stick to logical proportions. They also tend to be clear, symmetrical, and come with an attached handle.  They are built for function over form, but they are beautiful in terms of their professionalism.  Many come with built-in glass screens, creating up to 8 smaller holes for the smoke to pass through but large enough to hold the broken up cannabis and subsequently, the ash.  There is usually little unnecessary detail.  


Artisanal or “heady glass” bowls serve the same, basic function as scientific glass bowls, but they tend to lean more towards style than substance.  Built-in glass screens tend to be rare, and the inside depth of bowls can vary dramatically.  Their height and width have no standard size to conform to, and they aren’t necessarily transparent.  It’s creative free-reign with heady glass, artisanal bowls. offers glass bowls blown and coloured to look like anything from ice cream cones, to skulls, to trees with owls on the branches, to dice.  They all are available in both 14mm and 19mm ground-glass joint sizes.