A new congruent melting compound intermediate between the solid solutions of LiCaAlF6 and LiSrAlF6 is reported. When doped with Cr3+ ion, the new compound (Cr:LiSr0.8Ca0.2AlF6) has demonstrated room-temperature lasing in the spectral region from 750 to 950 nm. This material has mechanical properties similar to those of Cr:LiCaAlF6 and a broadband laser tuning range similar to that of Cr:LiSrAlF6. Long-pulse, flash-lamp-pumped lasing with 1.25% overall efficiency is reported by using a rod cut from an earlier boule.