“ Magnesium and incorporated water have been observed to play critical roles in nonclassical crystallization pathways of calcium carbonate , the dominant carbonate found in nature, through promoting formation of low energy metastable intermediates such as monohydrocalcite (CaCO3·H2O), ikaite (CaCO3·6H2O), and amorphous calcium carbonate (CaCO3·H2O).”