Google announced the Nexus 6P and the Nexus 5X yesterday. The 6P has a unibody anodized aluminum construction that comes in aluminum (silver), graphite (black), and frost (white) colors. But there is a fourth color, and it's only exclusive to Japan for now.
This is the gold colored Nexus 6P and as you can tell it looks quite stunning. Unfortunately, you will have to switch the website region to Japan to even see this image. As for the phone itself, there is no word on when, if at all, this color will be available in other regions.
Update: The phone is officially called Nexus 6P Special Edition.