Natural stone can be defined as a naturally occurring rock that fulfils certain qualitative criteria and is therefore extracted and processed by sawing and polishing to definite dimensions for use in the building, construction, monument, and tombstone industries. The variety of rocks used as natural stone products is large and limitations on their use are usually a result of their technical or aesthetical properties. Natural stone must be economical to quarry and process in order to be competitive on the market, which underscores the need for a careful and comprehensive exploration and quality assessment process for natural stone deposits. Exploration for natural stone is a systematic process, comprising several distinct methods that complement each other. The general exploration process consists of a desk study phase, prospecting, deposit evaluation, and additional studies such as test production and test marketing. The main steps in evaluation of a prospect are mapping, sampling, ground penetrating radar (GPR) measurements, and core drilling. This study evaluates the suitability of GPR as one of the major methods in the natural stone exploration process. The evaluation is based on GPR measurements together with other geological studies on a variety of rock types commonly used as commercial natural stones. The rock types chosen for this study are rapakivi granite, porphyritic granite, soapstone, migmatite, diabase, mica schist, and staurolite-andalusite-cordierite mica schist. The general natural stone exploration process is also discussed and reviewed.