The natural Turkish marbles, especially Usak Green (UG), Aegean Purple (AP), and Marmara White (MW) were, tested as shielding materials using standard gamma sources such as Co-60, Cs-137 and Eu-152. The experiment showed that UG, AP and MW are very effective shields against gamma-rays. The result for this experiment is that the gamma-ray attenuation coefficients of UG, AP and MW are almost equal for the energy range from 0.1 MeV to 1.4 MeV. Also, the elemental compositions of the natural UG, AP and MW marbles have been determined by fast and thermal neutron activation analysis and fourteen elements including Na, Mg, Al, Si, Cl, K, Ca, V, Ti, Mn, Fe, La, Ba and Sc have been found using the gamma spectroscopic method. The range of element contents of all Turkish marbles are remarkably different, but most of the elements are common such as Ca, Fe, Na, Cl, Mg, Si.