Investigation of structural behavior of colemanite depending on temperature

High temperature crystal chemistry and thermal behavior of the boron minerals bear special attraction, owing to the increase in their application areas requiring elevated temperature. Colemanite (2CaO center dot 3B(2)O(3)center dot 5H(2)O) is one of the most commonly found and used compound among the boron minerals. In this study, therefore, thermal and mineralogical characterization of the colemanite was performed by X-ray Diffractometer (XRD) and Thermal Gravimetric Analysis (TG-DTA). Also, mineralogical changes in crystal structure were measured and recorded during heating from room temperature up to its melting temperature for each 50 degrees C by using High Temperature XRD device. By this way, structural changes in the colemanite up to melting point were determined with increasing temperature for the first time. Results indicate that the thermal decomposition of colemanite has revealed a multi stage internal process; i) moisture removal, ii) dehydration-dehydroxylation, iii) amorphization of the crystal structure, iv) recrystallization of the amorphous solid (gradual reconstitutions).