These are Dyckia delicata cyanophylla.
They are big imposing plants as they live amid the forest.
This is the plant used to describe delicata, a shadowed plant.
But...but delicata cyanopgylla are always so. If you take it to full sun exposition it will stay so.
..or they will burn and die! these plant are used to clear and shadow environment. sun just get to them in moments they are not exposed to hours in a row to the blasting sun.
These are true delicatas accordingly to the description.
This is an odd strange and beautiful dyckia as dyckias are all made to face the sun.
this seems to contrary the firs Dyckia rule: sun!
Of course they get sun but always a filtered one.
The substrate is made exclusively by decomposed fallen leaves!
they are all on top of rocks!