I thought we were talking about the original image that nKoan linked Timex: What folks are talking about in this thread though, is that the blue/black combination is perceived as white/gold in a particular picture, largely due to the poorness of the photo and the lack of color context
In most instances, formal gowns tend to run rather small
Style D3816 features a sheer bodice that starts with elegant shoulder straps and dives into a deep plunging neckline, lined in illusion tulle
The hem is also asymmetric, so it at the front it falls to just below your knees, giving you room to kneel and move
Dark denim can also work when styled with leather shoes and a fitted shirt
For Black Tie Optional events, a very smart, dark suit with a conservative tie and white shirt can be acceptable if a tuxedo is genuinely not an option, but a tuxedo is always preferred