Upcoming Rockhounding Events in Georgia
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Amethyst
Quartz is one of the most common minerals found in the Earth’s crust. While it is usually colorless and transparent, quartz can also be found in a wide variety of colors and a range of opacity. These varieties generally have their own name such as rose quartz, amethyst, smoky quartz, and citrine.
Amethyst is a violet variety of quartz. The name comes from the Greek “amethysto” meaning not intoxicated, a reference to the belief that the stone protected one from drunkenness.
This semiprecious stone is often used in jewelry, especially due to its relatively high hardness.
The purple color of amethyst comes from impurities of iron, irradiation, and the presence of other trace elements. The hue can vary greatly from a light lavender to a deep purple.
Granite
Granite is the most common igneous rock in Earth’s continental crust. Granite can be found all around you in countertops, tiles, monuments, and more.
Granite is made up primarily of feldspar, quartz, and mica, with feldspar being the most prominent. Feldspar is usually white gray, pink, or red in color and features a visible cleavage pattern. The mica found in granite can include muscovite, biotite, or both.
Granite is formed by slowly cooling molten rock material. Because the process is so slow, the crystalline structures of the minerals that make up granite are able to grow quite large. Over time, granite is uplifted and revealed on the Earth’s surface via the erosion of overlying sediment.
Granite 23 by James St. John. This file is licensed under the Creative Commons Attribution 2.0 Generic license.
Author: Celeste
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