Moldable fluoroaluminophosphate glasses

An essentially dry alkali metal (R.sup.1) aluminofluorophosphate glass also containing at least one divalent metal oxide (R.sup.2) selected from the group of PbO, ZnO, CdO, MgO, CaO, SrO, and BaO which exhibits a relatively high viscosity at the liquidus, a low crystallization rate at the liquidus, a transition temperature below 350.degree. C., at least a "B" rating in a weathering test procedure comprising exposure for one week in an atmosphere of 98% relative humidity at 50.degree. C., a weight loss of less than 2 mg/cm.sup.2 after immersion for one hour in distilled water at a temperature of 95.degree. C., and demonstrates a viscosity no greater than about 10.sup.9 poises at temperatures below 400.degree. C., thereby displaying the capability of being molded at temperatures below 400.degree. C. into complex shapes, which consists essentially, as analyzed on an atomic basis, between about R.sup.1.sub.0.75 R.sup.2.sub.0.25 AlPF.sub.2 O.sub.4 and R.sup.1.sub.1.25 R.sup.2.sub.2.5 AlP.sub.5.5 F.sub.5 O.sub.16, and wherein said components are present in the following atomic ratios:

• ______________________________________ F:Al >2 but <5 P:Al >1 but <5.5 R.sup.1 :P >0.25 but <1.25 Pb:Al <1.25 Zn:Al <1.25 Mg and/or Ca and/or Sr and/or Ba and/or Cd:Al <1.25 Pb and/or Zn + (Mg and/or Ca and/or Sr and/or Ba and/or Cd):Al >0.25 but <2.5 (R.sup.1 + R.sup.2):P <1 ______________________________________