Way back in the 70s I used to set slender terminated quartz crystals
as the centers of lily-like flowers (long before I ever saw anybody
else do it!). I always had to use glue, as the crystals’ sides were
parallel to the bezel and there was no way to fold any part of it
over. However - I wonder why you want to cover the termination,
since you mention it - a mineralist would want to see it. Surely
there must be broken or damaged ones that wouldn’t mind being hidden.
A 1" indicolite sounds gorgeous.