Dissolution and precipitation behaviors of zircon under the atmospheric environment

Kitagaki, Toru  ; Yoshida, Kenta*; Liu, P.*; Shobu, Takahisa  

Zircon's degradation due to reactivity with aqueous solutions renders it difficult to read past records. Therefore, the reactive behavior of zircon in various acid-base solutions was examined under normal temperature and pressure conditions. A piece of zircon mineral was immersed in three different solutions: 0.1M HCl (aq), ultrapure water, and 0.1M NaOH (aq). Consequently, the reaction was limited when zircon was immersed in ultrapure water. In the case of the zircon immersed in 0.1M HCl (aq), Zr precipitated on the surface after the dissolution of ZrSiO. In the zircon immersed in 0.1M NaOH (aq), dissolved Zr and Si precipitated on the surface in the early stages. Subsequently, the dissolution of ZrSiO formed a porous layer, and most dissolved Zr precipitated as new zircon crystals.