Pemco Frit P-283 Cost/lb: $1.62 M.P./°F 1420 Silica/Alumina ratio: 22.0:1 Equivalent Molecular Weight: 344.200 Molecular Formula of Pemco Frit P-283: Na2O 0.922 Al2O3 0.199 SiO2 4.385 CaO 0.018 MgO 0.060 Percentage Analysis 76.50 % SiO2 5.90 % Al2O3 16.60 % Na2O 0.70 % MgO 0.30 % CaO _____________________ 100 % TOTAL Comments: 9.2 x 10-6 coefficient of thermal expansion (50-450° C) melting range of 1420-1670° F