Ключевые слова: colorful, corundum, crystal, dark, epidote, esoteric, gem, gemology, gemstone, geological, geology, green, macro, metamorphic, mine, mineral, mineralogy, natural, nature, object, precious, rare, raw, red, reflection, rock, rough, ruby, saualpite, science, semiprecious, specimen, stone, studio, uncut, unpolished, zoisite,