Ключевые слова: aggregate, black, bohemia, cluster, collect, collection, colorful, crystal, crystalline, czech republic, detail, fluorescence, fluorescent, gem, gemstone, geology, glow, green, hungary, hyalite, hydrothermal, isolated, isolated on black, isolated on white, matrix, mine, mineral, mineralogy, museum, natural, nature, opal, ore, pegmatite, precious, rock, rough, sample, science, silica, silica gel, silicon, silicon dioxide, specimen, stone, treasure, ultraviolet, uv, white,