I learnt to "read" the fascination of Castellani's monochrome surfaces a long time ago, but even now I like to turn the work around and observe the methodical, precise, complex "construction" that can be seen on its reverse. A work that is crazy to imagine, that calls for faith in one's own creativity, that verges on religiosity. In the rhythm that they will produce on the front of the canvas, the study and arrangement of the nails implies a deep concentration bordering on obsession for the final result. Castellani pursues the unlimited potentialities of a finite, monochrome surface: this quest was to remain constant and consistent through the years. As though before an immense horizon to be discovered and reinvented.
On his surfaces, each nail corresponds to two points: hollow and relief, light and shadow. A game that is endless, just as its solutions are infinite: as many as the rhythmic paths it is possible to imprint on his canvases. His works are the testimony of a complex investigation of light: the threedimensionality pursued with the system of the nails, plays entirely in favour of the surface, at the moment in which it is bathed in light. In fact, depending on the source of the light (and its quality: concentrated and direct rather than diffused) and the different points of observation, the work's reality is revealed as a space with a thousand possible readings. In a certain sense, "unfathomable" in its totality. Someone once commented that Castellani’s surfaces are spaces of contemplation, and I think this stems from the religiosity I mentioned earlier.
In Castellani's canvases the harmony of the rhythms combines perfectly with the concepts of space and time. Like in this Superficie bianca (White Surface) of 1966, of excellent provenance and great beauty. It offers infinite possibilities of interpretation, in the subtle contrast of light/dark, as well as in the dynamic nature of the multiple visual cross-references, from one side of the surface to the other, without a precise direction to follow, other than the one chosen by the viewer.