For Polvo, Varejão has created her own oil paints, named after thirty-three definitions of skin colour taken from the 1976 survey. The artist selected some of the more exotic and poetic terms, including Fogoió (Fox on Fire Red), Enxofrada (Angry Sulphur), Café com Leite (Milky Coffee), Branquinha (Snow White), Burro-quando-foge (Faded Fawn), Cor Firme (Steady Colour), Morenão (Big Black Dude), Encerada (Buffed) and Queimada de Sol (Sun Kissed).

Varejão also presents an installation of eleven self-portraits painted in an academic style using these paints. The skin tones in the paintings range in various shades from dark to light.

The artist has created a brand Polvo (Octopus) and a logo for the paints featuring an octopus, a creature famous for using its ink in defense. Octopus ink contains melanin, the same substance that gives colour to human hair and skin.

The artist's initial inspiration for these works comes from casta painting, a seventeenth- and eighteenth-century genre characteristic of New Spain and particularly prevalent in colonial Mexico. In the post-Conquest period, casta paintings sought to document the varieties of interracial mixing in the New World in an attempt to classify and frame racial diversity and hybridity through a complex casta system.

The casta system developed by colonial Spaniards helped establish and perpetuate a rigid hierarchical taxonomy based on notions of purity associated with whiteness. The concept was derived from the Latin castus, which literally means 'keep pure'. Using more than one hundred categories of racial intermixing, the casta system classified a broad spectrum of combinations of white, black, Indian and mixed-race heritage. Those considered 'pure bred' were recognised as part of the nobility and held greater economic and social power. Even at this early stage in Latin American history, those of black and mixed-race heritage occupied less privileged positions.

With Polvo Varejão emphasises how colour acts as a language and lexicon. These works allow us to rethink our own systems of chromatic classification and the social processes that are expressed through them.