In this paper we present a system for tactile object exploration. The system is built using a gripper with two parallel fingers, each equipped with a tactile array and a force/torque sensor. We have designed and implemented a set of exploratory procedures for acquiring the following properties: weight, shape, texture, and hardness. The system is successful at extracting these properties from a limited domain of objects. We present a detailed evaluation of the system and the causes of its limitations. The manipulation, motion, and, sensing primitives we have developed in the process of this work could be used for a variety of other tasks, such as model-based recognition, tool manipulation, and assembly.