Marlene Sketches Zeolite’s Molecular Rooms

Morning light cuts across Marlene’s sketchbook. Beside a small pale mineral specimen, she draws one tetrahedron, then another, joining them at their corners until a cage begins to hold together. A line goes astray. She redraws it, then shades the channel through the centre—not to fill it, but to make its openness visible.

In a zeolite, silicon and aluminium sit within tetrahedra of oxygen atoms. Shared oxygen corners link those units into a three-dimensional framework, leaving tiny, regular cavities and passages. Water and exchangeable cations can occupy those spaces; suitably sized molecules can enter while others are excluded. What looks like an absence is part of the mineral’s working structure.

Marlene turns the pencil sideways and softens the shading. The pale specimen offers no view into these molecular rooms; the sketch is a way of imagining their scale and arrangement. She leaves the cage open on the page. The solid lines matter, but so does everything they have carefully failed to close.