Carico Lake is a famous turquoise mine in Nevada known for its brilliant green turquoise. This is a pocket rock showing the characteristic green of Carico Lake.
 
This specimen weighs 281.7 carats and measures 5.5cm X 5cm X1.75cm. It is not treated and not backed. It is priced at $1 a carat or $282. I have assigned a TG  of 50 or MG Mid Grade. Pocket rocks like this specimen are rare. This specimen comes from the Callais Collection. White spot is camera flash.