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Abstract Quantum tokens are based on the fact that an unknown quantum state cannot be copied, since the measurement under an incorrectly chosen basis irretrievably destroys the quantum state (quantum no-cloning theorem). One of the most promising candidates for realization of solid-state quantum tokens are the color centers in diamond, for example nitrogen-vacancy (NV) centers. These atomlike defects exhibit quantum properties even at room temperature being protected by the dense diamond crystal lattice. The realization of a quantum token based on single NV qubits is technologically very challenging, as high precision in magnetic field alignment and positioning of the NV centers is required. An innovative approach applying ensembles of NVs can be used based on the quantum projection noise, which can reveal an unwanted copy attempt by an attacker. Thus, replacing the conventional copy protection guaranteed by the quantum no-cloning theorem. This would allow the implementation of a novel quantum token protocol that is technologically less demanding to realize and compatible with the highest security requirement authentication procedures. Still, the physical realization of such devices remains an open research problem, demanding further investigation. With this in mind, some of the basic steps towards token realization including the preparation of ensembles of NV centers, the design and fabrication of microwave antennas for electron spin manipulation and of photonic nanostructures to enhance photon collection efficiency will be presented in the current chapter.