A bearing apparatus, comprising: a radial bearing stator including a stator support ring (302, 304, 402, 404, 502, 504') and one or more superhard stator bearing elements (306a, 306b, 406a, 406b, 506c, 506d') mounted to the stator support ring (302, 304, 402, 404, 502, 504'), each of the one or more superhard stator bearing elements (306a, 306b, 406a, 406b, 506c, 506d') including a superhard stator bearing surface (310a, 310b, 410a, 410b); and a radial bearing rotor including a rotor support ring (304, 302, 404, 402, 504', 502) and one or more superhard rotor bearing elements (306b, 306a, 406b, 406a, 506d', 506c) mounted to the rotor support ring (304, 302, 404, 402, 504', 502), each of the one or more superhard rotor bearing elements (306b, 306a, 406b, 406a, 506d', 506c) including a superhard rotor bearing surface (310b, 310a, 410b, 410a) generally opposing the superhard stator bearing surface (310a, 310b, 410a, 410b); said bearing apparatus (400, 400', 400", 500') being characterized in that the one or more superhard stator bearing surfaces (310a, 310b, 410a, 410b) or the one or more superhard rotor bearing surfaces (310b, 310a, 410b, 410a) includes polycrystalline diamond; and the other of the one or more superhard stator bearing (410a, 410b) or the one or more superhard rotor bearing surfaces (410a, 410b) include a non-diamond superhard material, wherein the non-diamond superhard bearing surfaces form a single substantially continuous bearing surface. a radial bearing stator including a stator support ring (302, 304, 402, 404, 502, 504') and one or more superhard stator bearing elements (306a, 306b, 406a, 406b, 506c, 506d') mounted to the stator support ring (302, 304, 402, 404, 502, 504'), each of the one or more superhard stator bearing elements (306a, 306b, 406a, 406b, 506c, 506d') including a superhard stator bearing surface (310a, 310b, 410a, 410b); and a radial bearing rotor including a rotor support ring (304, 302, 404, 402, 504', 502) and one or more superhard rotor bearing elements (306b, 306a, 406b, 406a, 506d', 506c) mounted to the rotor support ring (304, 302, 404, 402, 504', 502), each of the one or more superhard rotor bearing elements (306b, 306a, 406b, 406a, 506d', 506c) including a superhard rotor bearing surface (310b, 310a, 410b, 410a) generally opposing the superhard stator bearing surface (310a, 310b, 410a, 410b); said bearing apparatus (400, 400', 400", 500') being characterized in that the one or more superhard stator bearing surfaces (310a, 310b, 410a, 410b) or the one or more superhard rotor bearing surfaces (310b, 310a, 410b, 410a) includes polycrystalline diamond; and the other of the one or more superhard stator bearing (410a, 410b) or the one or more superhard rotor bearing surfaces (410a, 410b) include a non-diamond superhard material, wherein the non-diamond superhard bearing surfaces form a single substantially continuous bearing surface. the one or more superhard stator bearing surfaces (310a, 310b, 410a, 410b) or the one or more superhard rotor bearing surfaces (310b, 310a, 410b, 410a) includes polycrystalline diamond; and the other of the one or more superhard stator bearing (410a, 410b) or the one or more superhard rotor bearing surfaces (410a, 410b) include a non-diamond superhard material, wherein the non-diamond superhard bearing surfaces form a single substantially continuous bearing surface.