Used coffee grounds are a good natural resource that can be recycled and reused in many different ways instead of just throwing away. Last year, for example, we wrote about German start-up Kaffeeform that mixed waste coffee grounds with a special recipe of biopolymers to produce beautiful coffee cups. In this article, we would like to tell you about a different approach to the use of waste coffee grounds realized by the Shanghai-based product designer Zhekai Zhang in one of his latest projects – the COFFIRE pendant light.
The COFFIRE is a porcelain light that features a unique finishing technique using waste 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.
During the low temperature firing process (700-1000℃ / 1300-1800°F), the interaction between the biodiesel and the sugar in the coffee grounds, which oxidizes to red matter, leaves a marble-like texture on the ceramic surface. Each texture is unique because it is influenced by many variables, such as temperature, humidity, coffee grounds density, etc.
The designer says that the aim of the COFFIRE project is to develop 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 a porcelain product. Compared to 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 sand pit by gas kiln to achieve mass production, solving the problem of 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.