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Earthen building materials are experiencing a renaissance in light of the climate crisis. To engineer high-performance sustainable and durable earthen materials for the 21st century, the importance of chemistry—and biology—cannot be underestimated. 

Biomineralization refers to the biological processes through which living organisms produce minerals. In recent years, biomineralizing microorganisms have been used to stabilize soil or to impart a self-healing or self-sealing mechanism to damaged cement and concrete materials. However, applications of biominerals in cement and concrete research can extend far beyond these applications. This article focuses on the biomineralization of calcium carbonate (CaCO3) and silicon dioxide (SiO2) and their past, present, and future potential applications in cement and concrete research. First, we review the mechanisms of CaCO3 and SiO2 biomineralization and the micro- and macroorganisms involved in their production. Second, we showcase the wide array of biomineral architectures, with an explicit focus on CaCO3 polymorphs and SiO2 morphologies found in nature. Third, we briefly summarize previous applications of CaCO3 and SiO2 biomineralization in cement and concrete research. Finally, we discuss emerging applications of biominerals in cement and concrete research, including mineral admixtures or raw meal for portland cement production, as well as other applications that extend beyond self-healing. 

Driven by the need for sustainable construction solutions, there is renewed interest in earth-based materials. Biopolymer stabilizers can enhance the rheological and structural properties of these materials to facilitate their use in 3D printing. This research examined the influence of sodium alginate on the stability, particle interaction, rheology, and 3D printability of kaolinite, a commonly found clay in soils deemed suitable for construction. Findings revealed that sodium alginate could boost electrostatic interactions to enhance the stability of kaolinite suspensions. This rise in repulsive potential energy could reduce storage modulus and yield stress by orders of magnitude. However, as the alginate content increased beyond its critical overlapping concentration (0.12 %–0.6 %), a reverse trend was observed, which was attributed to the formation of a three-dimensional polymer network. Furthermore, alginate addition shifted the “printability window” of kaolinite mixtures to higher solid contents, which has positive implications on the strength and shrinkage of the printable mixtures. 

Portland cement concrete, the most used manufactured material in the world, is a significant contributor to anthropogenic carbon dioxide (CO 2 ) emissions. While strategies such as point-source CO 2 capture, renewable fuels, alternative cements, and supplementary cementitious materials can yield substantial reductions in cement-related CO 2 emissions, emerging biocement technologies based on the mechanisms of microbial biomineralization have the potential to radically transform the industry. In this work, we present a review and meta-analysis of the field of biomineralized building materials and their potential to improve the sustainability and durability of civil infrastructure. First, we review the mechanisms of microbial biomineralization, which underpin our discussion of current and emerging biomineralized material technologies and their applications within the construction industry. We conclude by highlighting the technical, economic, and environmental challenges that must be addressed before new, innovative biomineralized material technologies can scale beyond the laboratory.