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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]
[9] The difference between 19th-century and 21st-century mining techniques and the type of ore sought is based on the grade of material being mined and the methods of mining which are used. Historically, hand-mining of gold ores permitted the miners to pick out the lode quartz or reef quartz, allowing the highest-grade portions of the lodes to ...
The Empress of Uruguay is the world's largest amethyst geode, standing at a height of 3.27 meters. It is open along its length and weighs 2.5 tons in its current state. It was discovered in 2007 in the Artigas department, Uruguay by the Uruguayan mining company Le Stage Minerals. Its estimated value is US $190,000, although it is not for sale. [1]
Very large amethyst and regular quartz geodes 'Crystal cave' is both an informal term for any large crystal-lined geode and also used for specific geoheritage locations such as the Crystal Cave (Ohio), discovered in 1887 at the Heineman Winery on Put-In-Bay, Ohio, the Cave of the Crystals (Mexico), and the Pulpi Geode, discovered in 1999 in Spain.
Phaneritic rock: Anorthosite from the Stillwater Igneous Complex (Neoarchean; Montana) Igneous textures include the rock textures occurring in igneous rocks.Igneous textures are used by geologists in determining the mode of origin of igneous rocks and are used in rock classification.
In geology, texture or rock microstructure [1] refers to the relationship between the materials of which a rock is composed. [2] The broadest textural classes are crystalline (in which the components are intergrown and interlocking crystals), fragmental (in which there is an accumulation of fragments by some physical process), aphanitic (in which crystals are not visible to the unaided eye ...
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
Like amethyst, heat-treated amethyst often exhibits color zoning, or uneven color distribution throughout the crystal. In geodes and clusters, the color is usually deepest near the tips. [46] This does not occur in natural citrine. It is nearly impossible to differentiate between cut citrine and yellow topaz visually, but they differ in hardness.