These are not exactly slabs, but they fit into the natural freeform organic shaped stones used for uniquely designed jewelry category.
The Turquoise is also known as Naco Turquoise, and it comes from the Nacozari Mine in Sonora, Mexico. The Nacozari Mine is permanently closed.
For more information about Turquoise click here.
And also see our blog Where Turquoise Comes From.