The authors present a novel method of fabricating crystalline gold nanoparticles used in plasmonic application. The preparation and characterization of monocrystalline Au nanoparticles embedded in an YBa2Cu3O7- matrix is presented as well as a future vision of structured particle arrangements by photolithographic procedures. To use these particles for biological applications the matrix must be dissolved. The realized dissolving procedure by citric acid solution is shown whereas the dissolution of the matrix is investigated by X-ray diffraction experiments and Energy-dispersive X-ray spectroscopy. Furthermore the spectral characterization by particle selection is illustrated based on microspectroscopy