Re: Bluestone
Most of the Bluestone I have worked is soft and sandy.
One time I found a chunk that must have been an old step tread. It was
15 x 20 x 60". It looked like Bluestone, had to be, but man it was hard.
As hard as any granite I've carved.
It reminded me of the two famous blue-ish sandstones quarried in the
hills around Florence(Italy). Most of the city is made of one or the
other. The streets are paved with it. I worked there with a carver
during my student days.
"Pietra Serena" is very close in color to our Bluestone and generally
soft and workable. It tends not to be as distinctly bedded as ours.
"Pietra Dura", on the other hand, is a totally different animal. Hard as
nails with hard quartz-like crystalized veins. Sometimes it is blue and
brown mixed together. The Strozzi Palace is a good place to see this
stone.
So, maybe some hard Bluestones make good sidewalk material.