When collecting fine Japanese porcelain, enthusiasts frequently encounter two primary decorative methods: Underglaze (*Shita-etsuke*, 下絵付け) and Overglaze (*Uwa-etsuke*, 上絵付け). Understanding the technical distinctions between these two methods reveals why Tousen-gama’s specialized underglaze creations hold such a distinguished place in modern ceramics.
Overglaze Enamels: Brilliant but Delicate
Overglaze decoration—famously championed by Kutani ware and vibrant Arita enamel pieces—involves firing the porcelain with a clear glaze first. Once cooled, brightly colored vitreous enamels (reds, yellows, golds, and greens) are painted on top of the smooth glaze and fired a second time at a lower temperature (approx. 700°C–800°C). While this allows for intense, jewel-like colors and metallic gold accents, the pigments remain physically exposed on the surface. Over time, friction from cutlery, washing, or stacking can scratch or wear away overglaze designs.
Underglaze Mastery: Permanence Beneath Glass
In contrast, Tousen-gama’s expertise lies in **Underglaze decoration** (primarily *Sometsuke* indigo and specialized mineral underglazes). Here, the master artist paints freehand onto the dry, unglazed biscuit clay using natural cobalt oxide (*Gosu*) or iron pigments. The piece is then dipped into a liquid feldspar glaze and fired at high temperatures (1200°C+).
During this intense firing, the glaze melts into a liquid sheet of protective glass, permanently sealing the painted design underneath. The pigment fuses with the clay body itself. The result is a smooth, glass-like finish that can never fade, flake, or scratch off, no matter how many times it is washed or used.
The Tousen-gama Underglaze Distinction
Painting underglaze requires absolute mastery; porous biscuit clay absorbs moisture instantly, meaning mistakes cannot be erased or painted over. Tousen-gama’s painters possess the extraordinary skill required to execute delicate gradients, soft shading, and fine line art in a single, confident stroke. By choosing Tousen-gama, British collectors gain the delicate painterly aesthetic of fine art combined with the robust, lifelong durability of sealed porcelain.
