Beader’s dictionary
Q
QUARTZ
The term "quartz" refers to a family of minerals within the group of silicates. Quartz composes 12% of the lithosphere (outermost shell) and is the most common mineral. Quartzs are divided into different categories, among them the macrocrystalline quartz (amethyst, citrine, rock crystal, quartz smoke, rose quartz, blue quartz, quartz cat-eye, iron-eye, falcon-eye and tiger-eye ) and microcrystalline quartz (chalcedony, carnelian, onyx, agate, chrysoprase, jasper and petrified wood).