This study aims to design stable and high-performance bricks for construction by developing geopolymers based on clay and potash extracted from the ashes of dried cocoa pods. For this purpose, three potash solutions of 100 g/l, 150 g/l, and 200 g/l were prepared by dissolving different masses of pellets derived from cocoa pods in water. These solutions were mixed with clay primarily composed of kaolinite, illite, and quartz, and the resulting paste was shaped using a hydraulic press. After demolding and drying at room temperature until a constant mass was achieved, the blocks underwent thermal treatment at 60？C, 80？C, 100？C, and 150？C. The thermally treated blocks were subjected to compression tests, capillary absorption tests, and X-ray diffraction analysis. The compressive strengths increased with potash concentration and thermal treatment temperature. From 100？C and a potash concentration greater than 100 g/l, the blocks were stable in water, with a water absorption capacity that decreased with increasing potash concentration. All these physical and chemical changes are due to the formation of new mineral phases between the particles. Starting from 80？C for a potash concentration of 150 g/l and from 100？C for 100 g/l, the blocks were stable in water with a compressive strength exceeding the prescribed value of 4 MPa for load-bearing walls. Therefore, they can be used in construction.
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