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The geode was found in a mine near the city of Artigas, known for its spectacular geodes and amethysts. It was extracted from the surrounding basalt in a complicated process that took three months. The top part was cut to allow for a view of the interior and the amethyst crystals that were on the top were sold.
An amethyst geode that formed when large crystals grew in open spaces inside the rock. The largest amethyst geode found as of 2007 was the Empress of Uruguay, found in Artigas, Uruguay in 2007. It stands at a height of 3.27 meters, lies open along its length, and weighs 2.5 tons. Amethyst is also found and mined in South Korea. [19]
A geode (/ ˈ dʒ iː. oʊ d /; from Ancient Greek γεώδης (geṓdēs) 'earthlike') is a geological secondary formation within sedimentary and volcanic rocks. Geodes are hollow, vaguely spherical rocks, in which masses of mineral matter (which may include crystals) are secluded.
The thin, radiant, six pointed star, or asterism, is created by incoming light that reflects from needle-like crystals of the mineral rutile which are found within the sapphire. The Star of India is polished into the shape of a cabochon , or dome, to enhance the star's beauty. [ 12 ]
Vugs, cavities and geodes are all examples of open-space filling phenomena in hydrothermal systems. Alternatively, hydraulic fracturing may create a breccia which is filled with vein material. Such breccia vein systems may be quite extensive, and can form the shape of tabular dipping sheets, diatremes or laterally extensive mantos controlled by ...
Prasiolite (also known as green quartz, green amethyst or vermarine) is a green variety of quartz. Since 1950, almost all natural prasiolite has come from a small Brazilian mine, [ citation needed ] but it has also been mined in the Lower Silesia region of Poland .
In geology and mineralogy, druse is a crystal habit represented by the coating of fine crystals on a rock fracture surface, [1] or vein or within a vug or geode. [ 2 ] See also
For example, amethyst is a purple variety of the mineral species quartz. Some mineral species can have variable proportions of two or more chemical elements that occupy equivalent positions in the mineral's structure; for example, the formula of mackinawite is given as (Fe,Ni) 9 S 8, meaning Fe x Ni 9-x S 8, where x is a variable number between ...