Carbon dioxide is often seen as public enemy #1 in the battle against climate change, but there are more dangerous substances for the environment. For instance, there is a substance called black carbon that is found in air pollution that absorbs one million times more energy from the sun than carbon dioxide, which means it is a potent contributor to the climate crisis.

In India, the production of traditional clay bricks is responsible for around 20 percent of black carbon emissions globally, according to CNN. Seeking to turn all that pollution into something productive, architect Teja Sidnal founded a startup called Carbon Craft Design (CCD) that extracts black carbon from polluted air and upcycles it into strong, stylish tiles.

To do this, CCD collaborated with Boston-based Graviky Labs, a company that has figured out how to convert carbon soot from cars and factories into sustainable products. Using a similar process, the companies are turning purified carbon into a carbon pigment, which can be mixed with cement and marble waste from quarries to produce handcrafted, monochromatic tiles.

As described by the folks over at EcoWatch, the word “craft” in the company name derives from the fact that the cement tiles are handmade by craftsmen using traditional, lower-carbon processes that have been used in India for more than 200 years. The process involves using a hydraulic press to produce the tiles rather than burning the tiles. This process requires just one-fifth of the energy to produce compared to vitrified tiles.

According to the CCD website, just one sustainable building tile contains at least 70 percent waste material and is the equivalent of cleaning 30,000 liters of air. On top of that, the tiles are also stronger than conventional cement tiles due to the higher carbon content.

“Anything that we build should be able to be reused or upcycled in some form or the other,” said Sidnal. “That is why we feel that any resource is not a waste. And now we feel that air pollution is just a resource that is not harvested.”