Abstract: Zinc sulfide (ZnS) single crystals and multi-grain ZnS crystals are suitable for many applications. The disclosed method produces ZnS single crystals or multi-grain ZnS crystals. More specifically, ZnS single crystals or multi-grain ZnS crystals of pure or substantially pure hexagonal wurtzite structure with sufficiently high purity and crystalline perfection to be used to fabricate components and devices including but not limited to optical components (useful in the infrared (IR) & visible spectrum range of 0.34-14 ?m), photoluminescence devices, cathode luminescence devices, electroluminescence devices, semiconductor devices, and IR laser gain mediums (in the wave length range of 1-5 ?m).