What’s 23 feet tall, eats smog, and makes jewelry for fun?
In Rotterdam this week, the designer Daan Roosegaarde is showing off the result of three years of research and development: The largest air purifier ever built. It’s a tower that scrubs the pollution from more than 30,000 cubic meters of air per hour—and then condenses those fine particles of smog into tiny “gem stones” that can be embedded in rings, cufflinks, and more.