Two series of novel phosphors based on parent compound CaYGaO₄ were developed. The first series was created by doping trivalent europium into the yttrium position in percentages ranging from 0.50–20. The samples exhibit one strong emission in the orange region of the visible spectrum one medium emission in the yellow and several weak emissions in the green and red. This series preforms well in elevated temperatures, which makes them good candidates for solid state lighting purposes. The second series was created by doping terbium into the yttrium position at percentages ranging from 0.50–20. This latter series exhibits two strong emissions in the green portion of the visible spectrum, and a few weak ones in the red. These, however have high thermal quenching which makes them not suitable for solid state lighting purposes. It should be noted that using just this host lattice alone, there are still many more possibilities for the development of other phosphors, and this work is only the very beginning.