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White veins in dark rock at Imperia, Italy. In geology, a vein is a distinct sheetlike body of crystallized minerals within a rock. Veins form when mineral constituents carried by an aqueous solution within the rock mass are deposited through precipitation. The hydraulic flow involved is usually due to hydrothermal circulation. [1]
According to KellerLynn, "Boxwork is a speleogen, forming when bedrock between preexisting calcite veins were preferentially weathered away as the cave developed." [ 1 ] Boxwork is commonly composed of thin blades of the mineral calcite that project from cave walls or ceilings that intersect one another at various angles, forming a box-like or ...
Gossan (eiserner hut or eisenhut) is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein. In the classic gossan or iron cap all that remains is iron oxides and quartz, often in the form of boxworks (which are quartz-lined cavities retaining the shape of the dissolved ore minerals).
Drift mining is the use of drifts to extract ore - in this case the drifts follow the vein. A "level" is a horizontal passage that branches off from a shaft and is used for access to the parts of the mine where the ore is being removed. In mines where the lodes have significant vertical extent there can be many numbered levels, one below the other.
Along an ore shoot, there is a rich gathering of different minerals within a vein. The veins can resemble a pipe, chimney or ribbon in structure and are displaced mainly vertically oriented but also can be horizontal with large veins extending approximately 30 m (100 ft) horizontally and 150 m (500 ft) vertically. [3]
Drift is a more general mining term, meaning a near-horizontal passageway in a mine, following the bed (of coal, for instance) or vein of ore. A drift may or may not intersect the ground surface. [3] A drift follows the vein, as distinguished from a crosscut that intersects it, or a level or gallery, which may do either. [4]
The epithermal vein deposit (EVP) is a type of mineral deposit that forms in the shallow subsurface, typically at depths of less than 1,500 meters below the Earth's surface. [1] These deposits are formed by hot, mineral-rich fluids that circulate through fractures and cracks in rocks.
Many stone types can be detected by ultrasound; Factors contributing to stone formation (as in #Etiology) are often tested: Laboratory testing can give levels of relevant substances in blood or urine; Some stones can be directly recovered (at surgery, or when they leave the body spontaneously) and sent to a laboratory for analysis of content