Being that I'm quite the newbie to beauty, I stumbled across the word 'duo-chrome' over at All Lacquered Up the other day in her coverage of Chanel's Fall 2011 collection. The polish in mention was Peridot. It is a gold/green color depending on the way the light hits it. Essentially, it reminds me of pewter.
Duo-chrome: A metallic nailpolish that is two different colors and/or a blend of two colors depending on how the light hits it.