Hidden Valley is a little known mine. The story is told in Turquoise in America Part Two 1910-1990 and Part Three The Stories of Turquoise 1990-2020.
 
This cab weighs 29.6 carats and measures 2.5cm X 2cm. It is priced at $40 a carat or $1184. It is not treated and backed. I have assigned a TG of 87 VHG Very High Grade. Hidden Valley is seldom found in the marketplace especially at this grade. I purchased this stone from Wayne Nelson.