This writer first saw the dress as gold and white, until glimpsing the image below — the actual dress as sold on the website of the UK retailer Roman Originals (which, for just 50 British pounds ...

Some viewers saw gold and white while others insisted the dress is blue and black. Some people claimed they could see either interpretation, but only one of them at a time.

As soon as it was posted on Tumblr, the photo of the black and blue — or white and gold — cocktail dress began creating rifts between friends and caused people to question their realities.

This dress was truly fit for a princess. A garment worn by the late Princess Diana was sold during the Unstoppable: Signature Styles of Iconic Women in Fashion event by Julien's Auction on Jan. 18.

In person, the dress is c learly blue and black. The lighting of the image, which has a bluish tint, appears to be what is throwing people's brains off.

The two-tone dress, left, alongside an ivory and black version, made by Roman Originals, that has sparked a global debate on Twitter over what color it is on display in Birmingham, England on Feb ...