The rare earth elements (REE) set consists of 17 chemical elements, that is the fifteen lanthanides, plus scandium and yttrium. "Compounds known as rare earth oxides (REO) are readily formed from rare earth elements as they are typically very reactive with oxygen in the ambient atmosphere" (Mo-Sci, 2023). Industries regarding "catalysts, glassmaking, lighting, and metallurgy, have been using rare earth elements for a long time. Such industries, when combined, account for 59% of the total worldwide consumption" (Mo-Sci, 2023). Newer application areas are concerning battery alloys and ceramics. For glass production, the addition of REOs changes the properties of glasses. "The ability to change the fluorescent properties of the glass is one of the most important uses of REO in glass" (Mo-Sci, 2023).