Royston is a district in Nevada consisting of three turquoise mines: Bunker Hill, Oscar Wehrend, and the main producer, Royal Blue. Royston is known for its beautiful colors ranging from deep green to rich, light blues set off by a heavy brown matrix. The Royston district is still producing some turquoise of high quality. It ranges from a 5-6 in hardness for the highgrade. This is one the best selling stones for our line of jewelry. This Turquoise is in very limited supply and the real good high grade is very rare.