Lithium Carbonate (LiCO3) is the best source of lithium for making glazes in ceramics. Lithium is a high temperature flux, which means that it causes glazes to melt at relatively high temperatures, and is typically used in small amounts (5% or less). Because it is alkaline, it tends to produce fluid glazes with glossy surfaces. Lithium carbonate reduces thermal expansion and increases a glaze’s firing range. Lithium also improves the brightness and durability of glazes.