Choose quartz beads and pendants for your jewelry applications from lemon quartz, multicolor rutilated quartz, rock crystal quartz, rose quartz, smoky quartz, and tourmalated quartz. This semiprecious gemstone family shares the same chemical composition (silicon dioxide) and similar physical properties. All semiprecious beads linked below are types of macrocrystalline quartz (crystals recognizable with the naked eye), just like citrine and amethyst. True quartz can be distinguished from glass by its birefringence (double refraction), hardness, and an absence of minute air bubbles (often contained in glass). The use of quartz dates back to at least ancient Rome. Since the Middle Ages, quartz crystal balls have been used to predict the future. Quartz is said to be the universal healing stone. Quartz crystals are reputed to promote hope, happiness, and optimism while awakening us to the beauty of nature.