1973 Large Chromatic Range, Warm and Cool, Color Study Signed Sally WinterI've rarely met an old art school color theory exercise I didn't like, but this one is other level, feeling like a finished work that veers into Op Art territory. Dated 1973 on reverse and signed by a Sally Winter, it was executed on a large sheet of gridded paper in what appears to be gouache though perhaps some combination of paint and marker. (Details give a good sense of both color and surface.) Very saturated color, very well done, quite