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Marble is a metamorphic rock consisting of carbonate minerals (most commonly calcite (CaCO 3) or dolomite (CaMg (CO 3) 2) that have recrystallized under the influence of heat and pressure. [1] It has a crystalline texture, and is typically not foliated (layered), although there are exceptions. In geology, the term marble refers to metamorphosed ...
Mining. Mining of sulfur from a deposit at the edge of Ijen 's crater lake, Indonesia. Mining is the extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agricultural processes, or feasibly created artificially in a laboratory or factory.
Carrara marble, or Luna marble (marmor lunense) to the Romans, is a type of white or blue-grey marble popular for use in sculpture and building decor. It has been quarried since Roman times in the mountains just outside the city of Carrara in the province of Massa and Carrara in the Lunigiana, the northernmost tip of modern-day Tuscany, Italy.
Quarry. A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to manage their safety risks and reduce their environmental impact. [1][2] The word quarry can also include the underground ...
The giant bucket-wheel excavators in the German Rhineland coal mines are among the world's biggest land vehicles. Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, [1] is a surface mining technique that extracts rock or minerals from the earth. Open-pit mines are used when deposits of commercially ...
Porphyry (geology) Porphyry (/ ˈpɔːrfəri / POR-fə-ree) is any of various granites or igneous rocks with coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate -rich, generally aphanitic matrix or groundmass. In its non-geologic, traditional use, the term porphyry usually refers to the purple-red form of ...
Lime (material) Lime is an inorganic material composed primarily of calcium oxides and hydroxides. It is also the name for calcium oxide which occurs as a product of coal-seam fires and in altered limestone xenoliths in volcanic ejecta. [1] The International Mineralogical Association recognizes lime as a mineral with the chemical formula of CaO ...
Alabaster is a porous stone and can be "dyed" into any colour or shade, a technique used for centuries. [13] For this the stone needs to be fully immersed in various pigmentary solutions and heated to a specific temperature. [13] The technique can be used to disguise alabaster.