Glasses comprising Bi203, ZnO B203 and optionally a colorant including an oxide of a metal such as iron, cobalt, manganese, nickel, copper and chromium are suitable to form hermetic seals in solar cell modules, architectural glass windows and MEMS devices. Glass frit and paste compositions suitable for flow and bonding to various substrates—glass, metal, silicon, in the temperature range of 400-500 degrees Centigrade. The broad compositional range in mole % is 25-70% Bi203, up to 65% ZnO, and 1-70% B203. Such glasses do not have batched in alumina or silica. Such glasses lack alumina and silica.