A deflecting prism for electromagnetic radiation, in particular for refractometer- and/or ATR-measurements, is part of a measuring configuration. The deflecting prism has a body produced in one piece from a mono-crystal. The body has at least two beam conductive surfaces on a side of the body opposite each other or circumferentially about the body and a measuring surface lying between the beam conductive surfaces or surrounded by the latter. The body further has at least one beam entry surface or a beam exit surface. Accordingly, the measuring surface lies on an elevation formed on the body, which crosses over via a ledge surrounding the elevation into the remaining part of the body. On the remaining part, the beam conductive surfaces and/or the beam entry surface or exit surface lie.