Divided vertically, there's
a neutral white field and one with a rich, almost glowing, earth hue like terre verte, raw sienna, or Italian brown pink — transparent fresco colors that give the series its name.
They're pretexts for Katz to try out color combinations, and to place figures first against
neutral (usually off -
white) backgrounds, then against even
fields of saturated color, and finally to cut away the backgrounds entirely, presenting the figures as freestanding cutouts.