Yungai is an area and a mine located in Hubei Provence, China. The story of the introduction of Chinese turquoise to the US market is told in Chapter Five of Turquoise in America Part Two 1910-1990 and in an article Turquoise in China Past and Present on the Blog of turquoiseinamerica.com.
 
This cab weighs 35.4 carat and measures 3cm X 2cm. It is priced at $25 a carat - $885. It is not treated and not backed. I have assigned a TG of 89 or VHG. I purchased this stone from Yuki Wang and cut the cab myself.