Optical glass composition, preform and optical element

22322252323232323 2323An optical glass composition contains, in % by mole, 0% or more and 25.0% or less of SiO, 20.0% or more and 40.0% or less of BO, 0% or more and 5.0% or less of LiO, 3.0% or more and 15.0% or less of ZnO, 0% or more and 10.0% or less of ZrO, 2.0% or more and 7.0% or less of TaO, 6.0% or more and 25.0% or less of LaO, 5.0% or more and 22.0% or less of GdO, 66.5% or less of LaO+GdO+BOand 26.0% or more of LaO+GdO, and has nd of 1.83 or higher and 1.86 or lower, vd of 43 or higher and 46 or lower and a liquidus temperature of 1300° C. or lower, and a preform and an optical element are formed from the optical glass composition.