In most recent accounts of the African city it is the relationship between the visible and the invisible which gives the city its identity and presence; the interplay between what can be seen and what surmised, between a first and a second city, a city that reveals itself and one which bathes itself in shadow, an apparently readable place that inverts into an occult space in which signifiers overheat and meaning cuts loose from the previously knowable. Particularly formative amongst such work on African cities have been Filip de Boeck's (2004) study of Kinshasa, and AbdouMaliq Simone's (2004a) examination of the spectral dimensions of African cities like Douala and Dakar.

In Johannesburg, it is rather, or at least in a related but unique vein, the intertwining of surface and depth – in its historical and psychic senses – that defines the life of the city. Surface and depth exist in a set of relations in which each relies on the existence of the other, in which they are entwined or enfolded, suggestive each of the other, interpenetrating, and separating out at different points.

Johannesburg, that is, is a city of surfaces, capitalist brashness – and one which carries with it, too, a subliminal memory of life below the surface, of suffering, alienation, rebellion, insurrection – captured, not least, in the figure of the black migrant worker. Existing beneath the surface, the orders of visibility of the metropolis signal that there can be no surface without an underground (Mbembe & Nuttall 2008). Mine dumps – man-made hills of gold dust, relics of the old gold mines on which Johannesburg was founded, heaving earth to the surface, the debris of wealth extraction, form the ubiquitous landscape of the city. Beneath it, marking the legacy of its origins, is a catacomb of tunnels left by gold mining.

It is a city with an underneath, built on the extraction of gold – a labour system that was based on a rigidly hierarchical racial division, an original violence, a city in which race was used as a weapon in the production of barriers and asymmetrical privileges. A place, too, where there has always been a tension between the apparent fixity of race and the potential unfixing of the commodity form (Mbembe 2004).