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Mulberry Downs Quarry
Mulberry Downs Quarry is a disused opencast tin mine in Cornwall, England, UK. Today the site is described as a 'chasm' being a steep or sheer-sided pit long and up to deep, and the quarry and immediate surroundings are heavily wooded. The quarry was designated as a Site of Special Scientific Interest (SSSI) in 1973 for its geological interest. History The mine, known as Mulberry Hill Mine and locally just as Mulberry Mine has been producing tin since Roman times. The tin deposit itself has been described as "best example of a stockwork tin ore deposit in Britain" The mine was part of the Lanhydrock estate, and there was sporadic mining between 1859 and 1916other sources give the year of closure as 1912 with a total of of tin being produced in this period. Although the mine is opencast, two adits were run from the base of the quarry, however the current depth of the workings is consistent with the water table measured at nearby boreholes and as there is not any record of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open-pit Mining
Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, is a surface mining technique of extracting rock or minerals from the earth from an open-air pit, sometimes known as a borrow. This form of mining differs from extractive methods that require tunnelling into the earth, such as long wall mining. Open-pit mines are used when deposits of commercially useful ore or rocks are found near the surface. It is applied to ore or rocks found at the surface because the overburden is relatively thin or the material of interest is structurally unsuitable for tunnelling (as would be the case for cinder, sand, and gravel). In contrast, minerals that have been found underground but are difficult to retrieve due to hard rock, can be reached using a form of underground mining. To create an open-pit mine, the miners must determine the information of the ore that is underground. This is done through drilling of probe holes in the ground, then plotting ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bronze
Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids such as arsenic or silicon. These additions produce a range of alloys that may be harder than copper alone, or have other useful properties, such as ultimate tensile strength, strength, ductility, or machinability. The three-age system, archaeological period in which bronze was the hardest metal in widespread use is known as the Bronze Age. The beginning of the Bronze Age in western Eurasia and India is conventionally dated to the mid-4th millennium BCE (~3500 BCE), and to the early 2nd millennium BCE in China; elsewhere it gradually spread across regions. The Bronze Age was followed by the Iron Age starting from about 1300 BCE and reaching most of Eurasia by about 500 BCE, although bronze continued to be much more widely used than it is in mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-renewable Resource Companies Established In 1859
A non-renewable resource (also called a finite resource) is a natural resource that cannot be readily replaced by natural means at a pace quick enough to keep up with consumption. An example is carbon-based fossil fuels. The original organic matter, with the aid of heat and pressure, becomes a fuel such as oil or gas. Earth minerals and metal ores, fossil fuels (coal, petroleum, natural gas) and groundwater in certain aquifers are all considered non-renewable resources, though individual elements are always conserved (except in nuclear reactions, nuclear decay or atmospheric escape). Conversely, resources such as timber (when harvested sustainably) and wind (used to power energy conversion systems) are considered renewable resources, largely because their localized replenishment can occur within time frames meaningful to humans as well. Earth minerals and metal ores Earth minerals and metal ores are examples of non-renewable resources. The metals themselves are present i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1859 Establishments In The United Kingdom
Events January–March * January 21 – José Mariano Salas (1797–1867) becomes Conservative interim President of Mexico. * January 24 ( O. S.) – Wallachia and Moldavia are united under Alexandru Ioan Cuza (Romania since 1866, final unification takes place on December 1, 1918; Transylvania and other regions are still missing at that time). * January 28 – The city of Olympia is incorporated in the Washington Territory of the United States of America. * February 2 – Miguel Miramón (1832–1867) becomes Conservative interim President of Mexico. * February 4 – German scholar Constantin von Tischendorf rediscovers the ''Codex Sinaiticus'', a 4th-century uncial manuscript of the Greek Bible, in Saint Catherine's Monastery on the foot of Mount Sinai, in the Khedivate of Egypt. * February 14 – Oregon is admitted as the 33rd U.S. state. * February 12 – The Mekteb-i Mülkiye School is founded in the Ottoman Empire. * February 17 – French naval forces under Charles R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sites Of Special Scientific Interest Notified In 1973
Site most often refers to: * Archaeological site * Campsite, a place used for overnight stay in an outdoor area * Construction site * Location, a point or an area on the Earth's surface or elsewhere * Website, a set of related web pages, typically with a common domain name It may also refer to: * Site, a National Register of Historic Places property type * SITE (originally known as ''Sculpture in the Environment''), an American architecture and design firm * Site (mathematics), a category C together with a Grothendieck topology on C * ''The Site'', a 1990s TV series that aired on MSNBC * SITE Intelligence Group, a for-profit organization tracking jihadist and white supremacist organizations * SITE Institute, a terrorism-tracking organization, precursor to the SITE Intelligence Group * Sindh Industrial and Trading Estate, a company in Sindh, Pakistan * SITE Centers, American commercial real estate company * SITE Town, a densely populated town in Karachi, Pakistan * S.I.T.E Indust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sites Of Special Scientific Interest In Cornwall
Site most often refers to: * Archaeological site * Campsite, a place used for overnight stay in an outdoor area * Construction site * Location, a point or an area on the Earth's surface or elsewhere * Website, a set of related web pages, typically with a common domain name It may also refer to: * Site, a National Register of Historic Places property type * SITE (originally known as ''Sculpture in the Environment''), an American architecture and design firm * Site (mathematics), a category C together with a Grothendieck topology on C * ''The Site'', a 1990s TV series that aired on MSNBC * SITE Intelligence Group, a for-profit organization tracking jihadist and white supremacist organizations * SITE Institute, a terrorism-tracking organization, precursor to the SITE Intelligence Group * Sindh Industrial and Trading Estate, a company in Sindh, Pakistan * SITE Centers, American commercial real estate company * SITE Town, a densely populated town in Karachi, Pakistan * S.I.T.E Indust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quarries In Cornwall
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 reduce their environmental impact. The word ''quarry'' can also include the underground quarrying for stone, such as Bath stone. Types of rock Types of rock extracted from quarries include: *Chalk *China clay *Cinder *Clay *Coal *Construction aggregate (sand and gravel) *Coquina *Diabase *Gabbro *Granite *Gritstone *Gypsum *Limestone *Marble *Ores *Phosphate rock *Quartz *Sandstone *Slate *Travertine Stone quarry Stone quarry is an outdated term for mining construction rocks (limestone, marble, granite, sandstone, etc.). There are open types (called quarries, or open-pit mines) and closed types ( mines and caves). For thousands of years, only hand tools had been used in quarries. In the 18th century, the use of drilling and blasting operations was ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
