1. An apparatus for determining an object material of which an object consists, comprising: an irradiator-receiver pair for irradiating the object and receiving a resulting radiation with a first polyfrequent effective spectrum, transmitted through the object or reflected from the object, in order to obtain a first intensity value, and for irradiating the object and receiving a resulting radiation with a second polyfrequent effective spectrum, transmitted through the object or reflected from the object, in order to obtain a second intensity value, wherein the first polyfrequent effective spectrum differs from the second polyfrequent effective spectrum; a provider for providing reference data for a plurality of predetermined materials; and a processor for associating the object material with one of the predetermined materials on the basis of the reference data, a combination value based on the first and the second intensity value, as well as at least one of the first and second intensity values, wherein the provider is formed to store, for each predetermined material, a characteristic curve associating a respective value for the combination value based on the first and the second intensity value, with values for the at least one of the first and second intensity values, and wherein the processor comprises a determiner for determining which of the characteristic curves a vector of the combination value as well as the at least one of the first and second intensity values, or a plurality of vectors of the combination value and the at least one of the first and second intensity values, obtained from a plurality of irradiations/detections on the object by the irradiator-receiver pair, lies closest.