KAYNITE...a quartz like crystal used for beads and gem work.
I visited one gem website that had a price of $900.oo-$1000.oo for
a 10ct stone of quality.
It can be hard to work with because of it's multi cleavages.
Usually blue it can also be green and appears worldwide.

Kyanite has been used for thousands of years.

So.....there you go...Floorkasp was spot on