This plant of a friend seems to only produce calyxes. Is this a genetic thing or could it also be due to some kind of stress? If it is because of genetics, do you think this could be worth saving by taking a cutting?
Cannabis growers tend to use the words bract and calyx interchangeably. In actuality, the little oval shape with hairs coming out is actually a bract. In cannabis the actual calyx is a sheath of cells around the thing that becomes the seed once fertilized.
A cannabis flower is just a collection of bracts. We tend to colloquially call the fat pair of little bracts that form at the base of the buds where they branch into leaves, the calyx
The bract is the outer leaves, whether the plant is seeded or not the calyx expands.
When someone says it’s a bract, it’s usually wrong, the term is calyx, but bract CAN be used since the petals in the outside aren’t usually pulled away, but on the ripe ones, they are.
Do you know the genetics of the plant? That looks like a "grinspoon" or "string of pearls" mutation. There's another version called willowing, but the leaves are twisted when it's that.
Check out the Dr. Grinspoon strain. That thing might be a pain to trim, but it should smoke great!