What is stucco or gebs carving in Moroccan plaster decoration?

Gebs (also written jebs or gypsum stucco) is the carved-plaster craft that gives Moroccan interiors their lace-like white upper walls. Maâlems — master craftsmen — apply a layer of soft lime-and-gypsum plaster to the wall, then, working fast while it is still damp and workable, carve directly into it with chisels and knives, cutting away the background to leave intricate raised patterns: interlacing geometry, flowing floral arabesques, and bands of Arabic calligraphy. As it dries it sets rock-hard, holding crisp, deep relief. Done well, a gebs panel looks impossibly delicate, like carved ivory or frozen foam, yet it is just plaster and skill.

Gebs occupies a specific zone in the classic Moroccan wall, and once you know the layering you see it instantly. The lower third or so of a wall is clad in zellige tilework (durable where people touch and lean); above that runs a band of carved gebs (the white, relief-carved register); and above that, often, carved or painted cedar at the ceiling. The Fes madrasas — Al-Attarine, Bou Inania — and the Ben Youssef Madrasa in Marrakech are the textbook places to study it, where the gebs is carved so finely it dissolves the wall into shadow and light. The muqarnas hoods over niches and arches are gebs too, worked into honeycombed three-dimensional cells.

It matters because plaster let craftsmen achieve, cheaply and at speed, the kind of dense, abstract, infinitely repeating ornament that Islamic art prizes. Stone carving is slow and costly; gebs could clad whole walls in glorious pattern far more quickly, and its softness allowed undercutting and depth that stone struggles with. The carved plaster, the tile below, and the wood above were all coordinated by the same geometric vocabulary, so a great room reads as a single unified composition rising from floor to ceiling. It is one of the clearest expressions of the Moroccan genius for surface decoration.

For travellers, gebs is the white relief you will photograph again and again without necessarily knowing its name. Look closely and you can often read how it was made — the flat carved-back background, the crisp raised pattern, sometimes traces of pigment where it was once painted or gilded. The craft is very much alive: restoration workshops and new luxury riads still employ maâlems who carve gebs by hand exactly as their predecessors did, and some run demonstrations. Naming it 'gebs' and understanding the tile-plaster-wood layering is the single most useful thing you can learn for reading a decorated Moroccan wall.