Ca₉CeOSi₆

Architectural potential

A cerium-doped calcium silicate fired at 1100 °C, 50 MPa at 2.67 g/cm³ — a plain white-grey post-Portland binder with no functional flags and an honest eighteen-per-cent cut in embodied CO₂ and energy against Portland cement. At 50 MPa the role is non-reinforced non-structural-topping: pavilion wall infills, landscape-wall blocks, floor screeds and toppings in retrofit work, and prefabricated cladding panels for light framed additions. The cement comparison carries the argument to a client with no colour premium — the pouring logic stays familiar, the formwork stays familiar, the binder itself shifts. A 1 kg workshop batch at €11.74 scales to a 5 kg ceiling, which begins to make panel-work realistic at the studio scale. Cerium in the matrix does quiet service: a slight UV-stability benefit over plain wollastonite and a small grain-refinement effect, neither promoted as a flagged innovation. Natural placements are garden-room plinths, thermal-wall infills in south-facing conservatories, and screeds in acoustic retrofits over timber sub-floors. The caveat is thermal: vitrification at 1100 °C means the kiln-free argument does not apply — this is a low-CO₂ cement, not an ambient binder — and a project has to be clear which trade it is making before it specifies the material into its structural drawings.

Material character

A clean neutral white-grey through the 52 mm depth, with only the faintest warm cast from the cerium fraction under daylight and a slight cream note where the slab meets raking light along the long edge. At 2.67 g/cm³ and 85×85×52 mm the slab sits two-handed on the bench, close in weight-register to a block of cured mortar of the same face and distinctly heavier than the cobalt-iron-foamed sibling from this same batch. The 1100 °C fire is just enough to drive a vitrified skin that edges toward a partial matte glaze without crossing into melt. Edges cold-cut, kerf powder-whitened. Fully opaque. Rings a slightly higher note than the flagship Ca4K4O18Si6 exemplar — same family, leaner flux register.