It's times like this that I wish I had some experience in gemmology - that way, I could tell you if this was the real thing or not.  I did do some research and my uneducated guess is that this is NOT real turquoise, but possibly howlite or some other imitation.  Regardless, it makes a great accessory to wear with that little black dress or just kicking around in your jeans.  It measures 17" long and the center square stone is 3/4" wide.  the beads are 6mm.  The necklace appears to be in good condition and looks really cool on!