D believes blue colour to be black colour, for any reason whatsoever. He has a garment shop. He sells one blue colour shirt to M, representing it to be black colour. M knows nothing about colours. M believes D and accepts the blue colour to be black colour. Later on M`s mother explains M that the colour of the shirt is actually blue and not black. It is a clear case of

This is misrepresentation, not fraud. D made a false statement ('blue is black') but believed it to be true - D genuinely thought blue was black. Misrepresentation requires a false statement made innocently without intent to deceive. Fraud requires intent to deceive. D's belief was honest (even if bizarre about colors), so there's no fraudulent intent. M can rescind the contract for misrepresentation but cannot claim damages for fraud.