Disclosed is a crystal material represented by a general formula (1) : (Gd 1-x-y-z La x ME y RE z ) 2 (Si 1-v MM v ) 2 O 7 (1), where ME is at least one selected from Y, Yb, Sc, and Lu; RE is a transition metal or rare earth element; MM is at least one selected from Ge, Sn, Hf, and Zr; and ranges of x, y, z, and v are represented by the following (i) or (ii): (i) 0.05 ‰¤ x + z ‰¤ 1.0, 0.0 ‰¤ y ‰¤ 1.0, 0.0001 ‰¤ z < 0.05, and v = 0.0 (where, when RE is Ce, y = 0 is an exception) or (ii) 0.0 ‰¤ x + y + z ‰¤ 1.0, 0.0001 ‰¤ z ‰¤ 0.05, and 0.0 < v. This configuration provides a crystal material having a large light emission amount and a short fluorescence lifetime and a radiation detector, an imaging apparatus, a nondestructive inspection apparatus, and a lighting apparatus containing the crystal material.
