Bothered by the waste caused by disposable face masks, many of which are made of polypropylene, the South Korean furniture design student has come up with an eco-friendly solution, melting them to make stools he calls “Stack and Stack”. “Plastic is recyclable, so why don’t we recycle face masks, which are made of plastic?” the 23-year-old said. In June, Kim set up a mask collection box at his school, the Kaywon University of Art and Design in Uiwang city, south of Seoul. He has since gathered 10,000 used masks, and has received more than a tonne of defective ones from a factory as well. The final result needs no glue or resin to hold it together and is completely made from the recycled personal protective equipment (PPE), with no added materials. Even the stools' marbled white, blue and pink patterns are derived not from added dyes or paints but simply from the colour of the original masks.