State Gem: Quartz
Quartz was designated as the state gem in 1976 by the state legislation. There were two forms that were designated, clear quartz and amethyst.
Quartz is the second most common mineral on the planet, next to feldspar. It is made up of silicon-oxygen tetrahedral where two of the oxygen atoms are shared in a continuous string to give us a formula of SiO2. It is a member of the trigonal crystal family, commonly forming in clusters and en masses. Common colored varieties include citrine, rose quartz, amethyst, smoky quartz, milky quartz, and others. The cryptocrystalline varieties are either translucent or mostly opaque, while the transparent varieties tend to be macrocrystalline. Chalcedony is a cryptocrystalline form of silica consisting of fine intergrowths of both quartz, and its monoclinic polymorph moganite. Other opaque gemstone varieties of quartz, or mixed rocks including quartz, often including contrasting bands or patterns of color, are agate, sard, onyx, carnelian, heliotrope, and jasper. The common gemstones from the quartz family found in Georgia are;
- clear quartz or rock quartz
- smoky quartz
- rose quartz
Exemplars of quartz-
Clear Quartz or Rock Quartz
Other forms of quartz are found in granite, jasper and agate. Example of the jasper are the Georgia Queen Picture Jasper, found in the Unidilla area of Georgia.
Another form of quartz can be found in the Savannah River agate which is found in the Girard, Georgia area along which chert with fossils embedded may be found.