AlOSi₅Zr₁₀

Architectural potential

A zirconium-silicate-alumina heavy-oxide ceramic fired at 1250 °C, 200 MPa of compression, and a specific thermal-mass register that earns its carbon debt only where the temporal-flywheel role is the point. Natural placements are south-facing trombe-wall infills in a high-desert pavilion, hypocaust slabs under a library reading floor, night-flush cooling cores in a gallery bay, and radiant-heat storage tiles behind a wood-burner in a rural dwelling. The material absorbs daytime solar gain slowly and releases it after dark — a thermal day-shifter rather than an insulator. The caveat is stark and has to frame the specification: at 326 per cent higher embodied CO₂ than clay brick and 108 per cent higher embodied energy, this ceramic cannot be used in bulk. It is a thin-tile solution, a patch across a conventional masonry assembly, a localised high-performance core inside an otherwise low-carbon wall. Specify it where the zirconium-grade thermal mass does something that clay brick cannot — a specific thermal lag, a specific re-radiation profile, a specific fire-resistance window — and let clay or earth do the bulk work elsewhere. 200 g workshop batches cap the project at signature scale.

Material character

A neutral cream-grey body with the flat opacity characteristic of a zirconia-heavy ceramic — no tonal depth, no translucency, a matter-of-fact surface that refuses to play with light. At 5.83 g/cm³ and 70×70×35 mm the slab is decisively two-handed — one of the denser ceramics in the palette, close in lift register to a basalt block of the same footprint. Surface carries the vitrified skin of a high-fire ceramic, satin-matte with a just-visible sinter grain under raking light. Edges cold-cut with a fine kerf powder. Against a conventional fired clay body the ring under tap is high, sharp, and distinctly metallic-edged.