An area at the back of the minster was displaying some new stonework and a board near to the carvings informed that:
New stonework copies the original stone and this is carried out by our 24 Masons, Carvers and Apprentices.
Occasionally the removed carving is too decayed to see what it used to be. When this happens our carvers use the same form and dimensions for the stone but create a new design inspired by their own research.
If you look closely at the labels underneath the carvings in the second picture you can see what each one depicts.
These are fantastic!!! So much hidden detail in the York cathedral!!!
It is an amazing place, I know you would love it