Analysis of the isothermal crystallization of CaSiO3 in a CaO–Al2O3–SiO2 melt through in situ observations

Crystal growth of Wollastonite (CaO·SiO2) in a 42CaO–10Al2O3–48SiO2 melt is observed in situ at 1320 ° C and 1370 ° C using a high-temperature confocal scanning laser microscope (CSLM). The crystallization is initiated by seeding the melt with Wollastonite particles, which is the primary phase at these temperatures and composition. At 1370 °C, a faceted growth form is observed, while at 1320 °C, dendritic, non-faceted growth occurs. The dendrite tip velocity is measured and compared with Ivantsov’s theory. The presented experimental technique proofs to be successful for characterizing isothermal crystallization of minerals in silicate melts.