Physical, optical properties and emission characteristics of heavy metal fluoride (HMF) glasses containing 1 mol% of Pr, Nd and Tb as dopants are reported. Room temperature absorption spectra have been determined from VIS to the NIR Photoluminescence spectra were recorded at 300 and 77 K to measure the stimulated emission cross-section of the laser transitions employing an Ar+ (487.9 nm) laser. The quantum efficiencies of the fluorescent levels of these optical glasses were determined from measured lifetimes of the recorded luminescent levels at room and liquid nitrogen temperatures.