This book is a comprehensive research wherein the multi-experimental and theoretical studies and followings for growing perfect single or mixed alkali earth fluoride systems are exposed in detail. The accent is put on single calcium fluoride grown from the natural mineral – Bulgarian fluorite – the purification of which is accomplished by developed original, highly efficient technique for removing oxygen contaminants and some rare earth impurities. The developed techniques allow a simultaneous growth of axial-symmetrical boules, representing solid solutions of mixed fluoride systems with different content, as well as large diameter single boules with desired optical properties. Elements, manufactured from the grown crystals, are testified successfully in the optical systems of various devices. The unique optical properties of these crystal systems provide their intransient significance for manufacturing variety of elements for the needs of vacuum ultraviolet-infrared optics, laser techniques, astronomy, lithography and spectrophotometry, holography and dosimetry.