From Limestone to Basalt: A New Route to Carbon-Free Cement

Cement production generates roughly 8% of global CO2 emissions, with nearly half stemming from the unavoidable chemistry of limestone conversion—a problem that efficiency improvements alone cannot solve. Using basalt and silicate rocks instead of limestone could eliminate these direct process emissions entirely. This matters because it addresses the fundamental chemistry of cement production rather than just improving energy use, potentially transforming one of the world's most carbon-intensive industries.