what to do with leftover hypertufa mix?
make a tufa-cairn 
stacked stones to me are fascinating. It’s a human thing, only we stack stones.
For me they say ‘I was here’ but all over the world they have different meanings.
It is for meditation in Buddhism, since it takes patience.
The Inuit call stacked stones inuksuit, you are on the right path or as a memorial for a beloved person.
In Aruba they are someone’s wishes
In Greece they are associated with Hermes, the God of travel
And others see it simply as a sculpture 