Structure characterization of CaCO3 in early formation stages by 3D electron diffraction

Automatic systems for 3D data acquisition and analysis have turned electron diffraction into a reliable method for structure characterization of sub-micrometric crystalline domains. Here we will show the application of this technique for the analysis of mAra, a modulated precursor of aragonite able to incorporate small quantities of Mg and sampled directly from drip water inside the Obstanser Eishöhle cold cave, Austria. Electron diffraction can be nowadays considered a mature method for the systematic characterization of carbonate crystalline seeds.