Abstract: A particle mixture for forming an enamel comprising particles of a first glass frit and particles of a second glass frit; wherein the first glass frit comprises greater than 5 wt % silicon oxide (SiO2) and less than 5 wt % boron oxide (B2O3); wherein the second glass frit comprises boron oxide (B2O3) and less than 5 wt % of silicon oxide (SiO2); and wherein both the particles of the first glass frit and the particles of the second glass frit have a D90 particle size of less than 5 microns. Also described is an ink comprising the particle mixture, methods of preparing the ink, an article formed using the ink, and a kit comprising particles of the first and second glass frit.