Amethyst Geode with Calcite Inclusion
A stunning amethyst specimen with a ~3-1/2" long calcite crystal centered within the hollow geode opening. The dazzling amethyst crystals have encrusted portions of the calcite crystal in a druzy formation, making it catch the light in a unique way. This is a special piece to add to any collection!
Location: Uruguay
Measurements: ~8" tall x 8-1/2" wide x 5-1/2" deep
Amethyst is a variety of quartz which owes its coloration to the presence of iron in the area of its formation. The word Amethyst is derived from ancient Greek meaning "intoxication". It was believed by both ancient Romans and Greeks, if they wore Amethyst or made their goblets of the material, it would help prevent them from becoming intoxicated. Amethyst has been used in jewelry making for centuries. Spectacular, priceless carvings dating to the ancient Egyptians are displayed in museums. Amethyst is found in many places around the world. However, the most beautiful Amethyst, displaying deep rich purple crystals are mainly in South America.
Calcite is one of the most common minerals which grows in a wide variety of different shapes, colors and translucencies. The mineral itself actually belongs to a calcite group of "related carbonates" that are "isomorphous" with each other. All members of the group crystalize in triangular formations, have perfect rhombohedron cleavages, and in transparent rhombohedrons, display strong double refractions. Aragonite and Calcite are similar in chemical composition (polymorphs) but are structured differently, with Calcite forming triangular crystallization and Aragonite forming orthorhombic crystals (three axes planes, at unequal lengths, and all three axes 90 degrees to one another. Unique Calcite formations are created inside the caves where calcium rich water penetrates the cavern's limestone enclosure and slowly drips and flows on top of itself, allowing for the formation of unique stalactite and other globular formations to be created. In this slow process, other minerals can intermix with each other, adding to the interest and forming unusual specimens, such as the one displayed.