In this paper, a novel sensing technique for material recognition is presented. This issue is actually particularly addressed due to its large application fields, such as, for example, humanitarian demining, recycling industry, or material processing. The proposed approach is based on the contact between the sensing unit and the surface of the unknown material: an intelligent prodder has been developed that stimulates the material surface and reads the response. The measurement procedure identifies a set of suitable parameters from the viscoelastic response and uses these parameters for material recognition and classifications. Both the stimulation and the sensing functions have been implemented using piezoelectric transducers. An experimental prototype of the system has been realized and characterized against a large set of materials of interest in the area of humanitarian demining, and the false positive rate has been determined for the set of considered materials. Experimental, in field, validations have also been performed.