Every piece in the Mono collection is built on the same two-part geometry, a softly curved top carried on straight legs with hard, angular edges. Kerstens, the Antwerp, Belgium studio founded by interior architect Andy Kerstens, has run that outline through seven pieces since 2022, with a side table, coffee table, console, and bench in stone, followed by a side table, coffee table, and console in cast glass. Proportion and symmetry set each form, and no piece carries applied ornament, which leaves all of the surface work to the material.

The stone editions are each carved from a single solid block by Belgian craftsmen. The side table came first in 2022, and the coffee table, console, and bench followed in 2024. Carving from one block removes any joint between top and legs, and the veining and layered deposits of the stone run continuously through the piece. Where a cut falls across the curve of a top, those strata are exposed as bands, so two benches cut to the same outline from different blocks finish with entirely different surfaces. The glass editions keep the same profiles but have no geological record to draw on. A cast piece reproduces its model closely, so Kerstens built the variation in at the start, refining wooden models and then altering them to carry small irregularities.

Across the two materials, the irregularity enters at opposite ends of the process. In stone it is already in the block and is uncovered by the cut. In glass it is introduced by hand at the model stage and then fixed by the cast. Light passing through the glass volume picks up the striations and textured surface and refracts into shifting patches of reflection and shadow that change over the course of a day. Because the imperfections are specific to each cast, two glass tables of identical outline throw different patterns, in the same way that two stone tables cut from different blocks show different veining.