Our Craftsmanship

Extra white kaolin, a white sedimentary clay rock, is combined with quartz and feldspar. This mixture is crushed, sieved, diluted, kneaded, and finally wrung out. The result is a stony blend that must be further processed in a kneading machine to transform into ceramic slip. At this stage, the material takes on an ivory-cream appearance, similar to bread dough. It is then filtered to remove excess water  before being thoroughly wrung out.

Depending on the quantity and complexity of the pieces, three different shaping techniques are used: manual casting, pressure casting, and manual calibration.

For small series and intricate, original shapes, the modeler creates a master mold, also called a “mother” or “core”,  in porous resin. This matrix is then used to produce multiple plaster molds, which are replaced regularly, as each can typically be used for fewer than 100 pieces. The liquid slip is manually poured into the mold, and after the excess slip is removed, the mold dries for about 30 minutes before the piece is carefully extracted.

Unlike manual casting, which uses liquid slip, pressure casting relies on powdered clay created by exposing the slip to high-temperature pulsed air. This powder is then shaped through isostatic pressing between two polyurethane molds, forming the top and bottom of the piece. As the powder compacts, it solidifies, making this technique ideal for mass production.

Manual calibration is used for small series, circular and complex shapes. The paste is first extruded into rolls, which are then pressed onto a rotating mold using a shaping tool, a calibre.

Regardless of the shaping technique used, each piece is then trimmed, mopped up, brushed and dried. At this stage, the delicate and particularly friable piece requires meticulous handling. During the trimming phase, additional elements such as handles or pouring spouts may be added using slip as an adhesive.

The first firing, know as the biscuit firing, takes place at 980 °C (1,796°F). This process solidifies the object while keeping it porous, allowing it to absorb enamel in later stages. Precision, delicacy and expertise are crucial here, as any handling marks will become permanent after firing. Once removed from the kiln, the pieces shrink by approximately 15%, maintaining uniform  proportions. They are then carefully dusted with compressed air.

At this stage, a second firing is sometimes performed to create porcelain biscuit pieces. In this case, the piece is fired at an even high temperature (1. 400 °C / 2,552° F) without enamel or decoration, resulting in a raw, unglazed porcelain finish.

The encounter of biscuit with enamel…

After the first biscuit firing, each piece undergoes manual or automatic enameling. The enameller immerses the biscuit-fired piece in a bath composed of feldspar and quartz. Due to its porosity, the biscuit absorbs all the moisture from the enamel, while a precise hand movement ensures an even application of the glaze. In some cases, a manual spray technique is used to coat specific areas. This glazing process transforms the piece into a vitrified, white, and translucent material. Once coated, each piece is left to air-dry thoroughly before being meticulously inspected with a brush prior to firing.

The second firing takes place at 1,380°C (2,516°F) with the enameled pieces carefully stacked inside the kiln, protected by refractory cases called “gazettes.” This high-temperature firing in a reducing atmosphere triggers a deep vitrification process, permanently bonding the glaze to the porcelain body. Once removed from the kiln, each piece undergoes manual or automatic polishing, followed by a rigorous selection process to retain only first-choice pieces.

After the second firing, the decoration process begins, bringing each piece to life through chromolithography, hand painting, or spray application. Another specialized technique, known as band gilding, is used to apply delicate bands along the rims of plates. The piece is carefully centered on a rotating wheel, allowing for the precise application of uniform lines.

The final and third firing takes place at temperatures ranging from 800 to 1,200°C (1,472 to 2,192°F). This crucial step fuses the decorative oxides into the enamel, ensuring exceptional durability and resistance for everyday use. The result is a non-porous, resonant, hard, and translucent ceramic—each piece unique in its design and craftsmanship.

The Non Sans Raison Signature: A Mark of Excellence

The Non Sans Raison stamp is more than just a signature—it is a declaration of our relentless pursuit of perfection and a tribute to the renowned porcelain craftsmanship of Limoges. Our commitment to authenticity is reflected in every detail: masterful handcrafting, precise firing temperatures, meticulous attention to detail, and the refined balance of precious metals and flawless finishes.

Lightweight, translucent, and crafted from the finest extra-white kaolin, our porcelain is as durable as it is delicate. Dishwasher safe, designed for everyday elegance.

Authentic Limoges porcelain. 100% French craftsmanship.