big well formed aquamarine crystals on matrix rock

aquamarine beryl birthstone blue crystal crystalline crystallisation crystallization crystallography crystals diagenesis dioxide formation gem gemology gemstones geologic geological geology geomorphology igneous inorganic isolated jewel jewellery lapidary macro macrocrystalline march matrix metamorphic mineral mineralized mineralogy natural petrology precious quartz rare raw rock silica silicate silicon starstone stone unpolished vitreous volcanic