If I have to choose one main statement jewelry piece, I think it would be a cuff or bangle.  They can easily make an outfit chic and sassy.  I've been having an eye on the Givenchy bracelet for a while now, it's just a matter of crossing path with it.  Enjoy!
1- 
Dannijo, 2- 
Turquoise Stone Cuff, 3- 
Marc by Marc Jacobs, 4- 
Samantha Wills, 5- 
Bernard Delettrez, 6- 
Armani Exchange, 7- 
Vince Camuto, 8- 
Givenchy.