Ceramics is an ancient industry going back thousands of years. Humans have been glazing their ceramics since as far back as the 8th century BCE. While early civilizations used mixes of ash or soda and sand to glaze their pottery, today most glazing is done with the help of glass and oxide mixes, or lead.
However, there are certain drawbacks to using these glazing materials. The metal and lead glazes are often harmful for the environment. When glazed ceramics are used as utensils, they can potentially leach into food and drinks and cause metal poisoning.Now, a designer is exploring more sustainable options for ceramic glazing. Sinae Kim has developed a way to glaze ceramics with the help of human urine.
Kim collected urine for over five months for this experiment. She then distilled the urine by evaporating its water content, leaving a dark solution behind. The resulting mixture was filtered to extract a mineral paste, which she then used in glazing pottery.
The results, Kim found, were remarkable. Since minerals found in urine are the same minerals that can be found in some glazes and clay, they transformed into a glossy, opaque coating on the ceramic surface. Kim has glazed tiles and pots with urine to show its potential in being a more sustainable and less hazardous glazing material.