Ключевые слова: aggregate, amethyst, april, birthstone, complex, crown, crystal, crystalline, dioxide, energy, felsic, gem, gemmy, gemstone, geology, hydrothermal, jewel, mineral, mineralogy, natural, power, precious, purple, quartz, quarz, raw, rock, rock crystal, sacred, sample, scepter, silica, silicate, silicon, silicon dioxide, sio2, specimen, starstone, stone, transparent, treasure, unpolished, violet,