Siderite nucleation pathways as a function of aqueous solution saturation state at 25 °C

The mechanisms of siderite (FeCO3) nucleation from aqueous solution depend on the fluid saturation state. In this study we investigate effect pathway siderite. Thereof, performed a series turbidity and batch experiments. Turbidity measurements indicate that at low indices (SI < 3.69), proceeds via direct crystalline fluid. precipitation is confirmed by X-Ray diffraction (XRD) analysis. This first to report near-equilibrium conditions. At higher ≥ initial amorphous ferrous carbonate (AFC) followed growth XRD spectra confirm AFC its transformation Such differences in mechanism likely affect both reactivity resulting isotopic composition. Insight into state during could thus be crucial for accurate interpretation signature natural systems.