ER3+-doped soda-lime silicate glass: Artificial pink gemstone

Abstract

Er3+-doped soda-lime silicate glasses of the composition (in mol%) (65-x)SiO2:25Na2O:10CaO:xEr2O3 (where x = 0, 1, 2, 3, 4 and 5) were fabricated by conventional melt quenching technique. The physical and optical properties were measured and investigated. The erbium oxide enters the glass network as a modifier by occupying the interstitial space in the network and generating the NBOs to the structure. The molar volume increases with an increase in Er2O3 content, which is attributed to the increase in the number of Non-Bridging Oxygen (NBOs). The increase of NBOs in the structure generally leads to an increase in average atomic separation. The density, molar volume and refractive index of glasses increased linearly with increasing Er2O3 concentration. The color of glasses was changed from light pink to intense pink as the Er2O3 concentration was increased from 1 to 5 mol%. The Vickers hardness of Er3+-doped glasses was found to be in the range of 450-500 HV. In this study, it can be concluded that the soda-lime silicate glasses doped with high Er2O3 concentration has intense pink color and high value of hardness which is suitable to be cut as gems. ©2012 Science Publication.