Williamsburg Permanent Lemon

Just a little note that at first we thought this was a single pigment, however, this color contains viridian as well as a Hansa yellow.

“Very tart, greenish, acidic, brilliant yellow.” -Williamsburg

As a mixture, this color does not appear to have been specifically mentioned, however it is worth noting that Golden published groundbreaking lightfastness testing in various white colors. The choice of mixing white may affect the performance of certain pigments. See https://justpaint.org/astm-lightfastness-testing-for-oil-paints/ for more information.