Making cement from a different type of rock could clean up emissions

Researchers say Portland cement made from basalt could cut emissions by avoiding the direct CO2 released when limestone is processed.

The current basalt-based method still uses more energy than conventional cement production, so it is not yet the cleaner option.

The team says better mineral separation, clean electricity, and recovery of valuable metals like iron and magnesium could make the process viable.

Because cement is one of the hardest industries to decarbonize, this approach could offer an important low-carbon alternative.