Radioactive fissile isotope ratio analysis techniques that could potentially be used to uniquely identify covertly marked cards in play include:
1. Neutron activation analysis: This technique uses the emission of gamma rays from radioactive isotopes to identify the specific elements present in the card. By measuring the ratios of different fissile isotopes, such as uranium-235 or plutonium-239, it may be possible to detect subtle differences in the composition of marked cards.
1. Neutron activation analysis: This technique uses the emission of gamma rays from radioactive isotopes to identify the specific elements present in the card. By measuring the ratios of different fissile isotopes, such as uranium-235 or plutonium-239, it may be possible to detect subtle differences in the composition of marked cards.