Mn₄S₄Sb₄
sulfide metal composite · sulfide low tempMn4S4Sb4 is a sulfide metal composite suitable as sulfide low temp. Color: yellow-orange. Fired at 130°C from 3 precursors (Sb2O3, MnO2, S). Workshop batch: 300g at €9.01. Compressive strength ~150 MPa; estimated 0.09 kg CO₂/kg (-89% vs Portland cement). Notable: forms without a kiln. Confidence: medium.
- forms at
- 130 °C · hotplate · no kiln
- replaces
- portland cement
- CO₂
- 89.1% lower than Portland cement (0.09 vs 0.83 kg CO₂/kg)
- energy
- 89.1% lower than Portland cement (0.60 vs 5.50 MJ/kg)
- compressive
- 150 MPa
- density
- 6.58 g/cm³
- crystal
- monoclinic
- band gap
- 0.01 eV
- cost
- €30.03/kg · €9.01 / 300 g batch
- confidence
- medium (synthesis route)
- potential
- 0.70 · env 1.00 · novel 1.00 · struct 0.30 · lineage 0.50 · supply 0.19
- flags
- zero kiln: Forming happens without firing — the material cures through chemistry at ambient or hotplate temperature. At building scale this removes the kiln from the supply chain: on-site casting, regional workshops, cold-country fabrication all become available.
Architectural potential
A hotplate-cast compression piece at the heavier end of the sulfide palette, with 150 MPa of compressive strength and an eighty-nine-per-cent cut in embodied CO₂ against Portland cement. The chemistry cures at 130 °C, so the making sits in a warm studio rather than a kiln yard: drop-cast into plywood or silicone moulds, poured against timber substrates, pressed from a manganese-antimony-sulfide gel. Natural placements are detail-scale pieces where weight and compression matter but primary structure is carried elsewhere — cast thresholds in retrofit carpentry, heavy inlay tiles for gallery floors, sill blocks at south-facing window reveals, skirting and plinth runs in exhibition architecture. The yellow-orange face invites a decorative reading, so it is well-suited to places where a warm interior accent is wanted alongside mass. The cement comparison is the argument: similar compressive register at roughly a tenth of the carbon cost, with the kiln removed from the supply chain. The caveat is reach — at 300 g per batch and a 1 kg workshop ceiling, repeated tile runs are possible but a full floor is not, and the antimony content calls for ventilated saw-cutting and waste capture. Specification belongs to signature detail work rather than bulk cladding or slab-work.
Material character
The slab reads a saturated yellow-orange with copper undertones from the antimony–manganese sulfide matrix, warmer and more pigmented than the paler polysulfide siblings. At 6.58 g/cm³ in a 70×70×31 mm piece, the body is noticeably dense for its footprint — a firm two-handed lift despite the modest top face, closer in hand-feel to a small cast-iron tile than to a ceramic one. Surface mold-matte with the faint meniscus sheen of a hotplate cast; edges come as-cast, slightly crisp, catching light along the kerf. A fine sulfur bloom settles unevenly across the face, legible only under raking light. Opaque through the full depth, with a low acoustic note under the knuckle.
Recipe
300 g batch · peak 130 °C| element | precursor | formula | mass | safety |
|---|---|---|---|---|
| Mn | manganese dioxide | MnO2 | 37.36 g | moderate |
| Sb | antimony trioxide | Sb2O3 | 62.64 g | moderate |
- Pre-heatHotplate to 150 °C
- MeltSulfur liquefies at 115 °C; full liquid at 130 °C
- CastPour at 140–145 °C
- SetRoom temperature 30 min (firm) → 24 h (full strength)
Zero-kiln process — 130 °C hotplate cast only