It is well established that skin lightness-darkness is associated with social outcomes, but little is known regarding the social salience of skin undertones (redness and yellowness). Our study addresses two related research questions on this topic: first, we ask whether red and yellow undertones are consistently perceived by observers; second, we ask whether red and yellow undertones are associated with expectations of discrimination across a range of social settings. We address these questions using novel survey data in which skin lightness-darkness and undertones are captured using CIELAB measurements and a two-dimensional categorical skin color scale. Although we find skin lightness-darkness to be the strongest and most consistent predictor of discrimination expectations, respondents also perceived skin undertones consistently, and skin yellowness was associated with a higher predicted likelihood of discrimination net of lightness-darkness in certain social settings. Our findings suggest that colorism can extend beyond a light-dark binary and emphasize the value of capturing undertones, particularly yellowness, in social surveys assessing skin color.