Bisbee is an iconic turquoise mine considered on ot the Big Three of Arizona. The history is found in Turquoise in America Part Two 1910-1990.
 
This cabochon weighs 12.9 carats and measures 2cm X 1cm. It is priced at $150 a carat or $1935. It is not treated and backed. I have assigned a TG of 94 or GG. Bisbee of this grade with this provenance is difficult to find at any price. I purchased this from Bruce Mead who cut the stone.