what was its actual colour?
It was eventually confirmed as black and blue.
The dress
 Although the colour of the dress was eventually confirmed as black and blue, the image prompted many discussions, with users debating their opinions on the colour and how they perceived the dress in the photograph as a certain colour. Members of the scientific community began to investigate the photo for fresh insights into human colour vision.
where did the blue and black dress come from The photo originated from a washed-out colour photograph of a dress posted on the social networking service Facebook.
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The dress [SEP] Introduction
Although the colour of the dress was eventually confirmed as black and blue, the image prompted many discussions, with users debating their opinions on the colour and how they perceived the dress in the photograph as a certain colour. Members of the scientific community began to investigate the photo for fresh insights into human colour vision. The dress itself, which was identified as a product of the retailer Roman Originals, experienced a major surge in sales as a result of the incident. The retailer also produced a one-off version of the dress in white and gold as a charity campaign.