A scintillation crystal can include Ln(1-y)REyX3, wherein Ln represents a rare earth element, RE represents a different rare earth element, y has a value in a range of 0 to 1, and X represents a halogen. In an embodiment, the scintillation crystal is doped with a Group 1 element, a Group 2 element, or a mixture thereof, and the scintillation crystal is formed from a melt having a concentration of such elements or mixture thereof of at least approximately 0.02 wt. %. In another embodiment, the scintillation crystal can have unexpectedly improved proportionality and unexpectedly improved energy resolution properties. In a further embodiment, a radiation detection apparatus can include the scintillation crystal, a photosensor, and an electronics device. Such a radiation detection apparatus can be useful in a variety of applications.