When i saw this image of SJP in a amethyst waterfall dress in Marie Claire Greece (sorry couldn't find the original source for better quality) my heart skipped a beat. I absolutely adore deep aubergine and plum shades with a pop of turquoise.
I found a much better example of Purple hues teamed with gorgeous turquoise accessories, as seen here on super babe, Cameron Diaz at the Costume Institute 2007. Doesn't she look amazing?