The turquoise used in this cuff is called Lone Mountain. Lone Mountain turquoise has only been mined six of the past twenty-eight years. The mine produces turquoise of a unique color that we don't often see. I'll try my best to describe it, it's as if light cyan (#E0FFFF) was mixed with light cobalt (#88ACE0). I gave you the hex codes if you're into this sort of thing. In either case, it's a very unusual color.
Also, note that the sterling silver cuff has a thicker gauge than normal and has a mirror-like finish. That makes this cuff the perfect frame for the Lone Mountain turquoise.
When it came to composition, Shirley knew when to leave well enough alone. Which is what I will do right now.