Designer Zhekai Zhang has created a method of coloring porcelain with used coffee grounds and has applied it to his collection of lamps called COFFIRE.
Text description provided by the designer: How waste can be turned into something useful and beautiful? The COFFIRE project through the innovation of porcelain surface finishing technique by using used coffee grounds as sustainable coloring material to form mimic textures of marble under the mass production scenario. The eco-conscious method of staining is inspired by the ancient pit firing technique for pottery making in China. During the low temperature (700-1000℃) firing process, the interaction between the biodiesel and the sugar in the coffee grounds, which oxidized to red matter, leave on the surface of the ceramics to form random texture, because the surface texture is influenced by many variables, such as temperature, humidity, coffee grounds density, etc.
COFFIRE project developed the ‘imperfect’ design language from the perspective of the relationship between industrial standardized production and craftsmanship. This is a completely new and sustainable staining technique for porcelain products. Compared with the traditional pit firing, which tends to use toxic metals as coloring materials, the coffee grounds coloring ensures the safety of the product. In addition, this project replaces the traditional sandpit by gas kiln to achieve mass production, solving the problem of a high waste rate of traditional pit firing. Also, the translucency of porcelain can add a form of presentation to the texture effect of the surface.