This explains how the blue black white gold dress illusion was possible. But it doesn't explain why some people saw it one way and some saw it the other, and no one seemed to see Rose Gold Dresses for Prom, Weddings & More Quick Delivery Oh Hello Clothing The actual dress was black and blue. The confusion came from how lighting and color perception tricked people's brains, making some see it as white and gold. It became a viral example Woman discovers the iconic 'Optical Illusion Dress' that went viral in 2015 at yard sale Times of India Blue and black or white and gold? A decade later, it turns out the ultra viral optical illusion dress was also a boon to scientific advancement. See link below