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Carved Stone
Stone carving is an activity where pieces of rough natural Rock (geology), stone are shaped by the controlled removal of stone. Owing to the permanence of the material, stone work has survived which was created during our prehistory or past time. Work carried out by paleolithic societies to create stone tools is more often referred to as knapping. Stone carving that is done to produce lettering is more often referred to as lettering. The process of removing stone from the earth is called mining or quarrying. Stone carving is one of the processes which may be used by an artist when creating a sculpture. The term also refers to the activity of stonemason, masons in dressing stone blocks for use in architecture, building or civil engineering. It is also a phrase used by archaeologists, historians, and anthropologists to describe the activity involved in making some types of petroglyphs. History The earliest known works of representational art are stone carvings. Often marks carve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stone Sculptor At Work
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the crust, and most of its interior, except for the liquid outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathering, transport, and deposition of existing rocks. Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeologist
Archaeology or archeology is the scientific study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, architecture, biofacts or ecofacts, sites, and cultural landscapes. Archaeology can be considered both a social science and a branch of the humanities. It is usually considered an independent academic discipline, but may also be classified as part of anthropology (in North America – the four-field approach), history or geography. Archaeologists study human prehistory and history, from the development of the first stone tools at Lomekwi in East Africa 3.3 million years ago up until recent decades. Archaeology is distinct from palaeontology, which is the study of fossil remains. Archaeology is particularly important for learning about prehistoric societies, for which, by definition, there are no written records. Prehistory includes over 99% of the human past, from the Paleolithic until the adv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ductile
Ductility is a mechanical property commonly described as a material's amenability to drawing (e.g. into wire). In materials science, ductility is defined by the degree to which a material can sustain plastic deformation under tensile stress before failure. Ductility is an important consideration in engineering and manufacturing. It defines a material's suitability for certain manufacturing operations (such as cold working) and its capacity to absorb mechanical overload.. Some metals that are generally described as ductile include gold and copper. However, not all metals experience ductile failure as some can be characterized with brittle failure like cast iron. Polymers generally can be viewed as ductile materials as they typically allow for plastic deformation. Malleability, a similar mechanical property, is characterized by a material's ability to deform plastically without failure under compressive stress. Historically, materials were considered malleable if they were am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardness
In materials science, hardness (antonym: softness) is a measure of the resistance to localized plastic deformation induced by either mechanical indentation or abrasion. In general, different materials differ in their hardness; for example hard metals such as titanium and beryllium are harder than soft metals such as sodium and metallic tin, or wood and common plastics. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, hardness can be measured in different ways, such as scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics, concrete, certain metals, and superhard materials, which can be contrasted with soft matter. Measuring hardness There are three main types of hardness measurements: ''s ... [...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 strength, ductility, or machinability. The 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 modern times. Because historical artworks w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wear
Wear is the damaging, gradual removal or deformation of material at solid surfaces. Causes of wear can be mechanical (e.g., erosion) or chemical (e.g., corrosion). The study of wear and related processes is referred to as tribology. Wear in machine elements, together with other processes such as fatigue and creep, causes functional surfaces to degrade, eventually leading to material failure or loss of functionality. Thus, wear has large economic relevance as first outlined in the Jost Report. Abrasive wear alone has been estimated to cost 1-4% of the gross national product of industrialized nations. Wear of metals occurs by plastic displacement of surface and near-surface material and by detachment of particles that form wear debris. The particle size may vary from millimeters to nanometers. This process may occur by contact with other metals, nonmetallic solids, flowing liquids, solid particles or liquid droplets entrained in flowing gasses. The wear rate is affected by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant typically need an additional 11% chromium. Because of its high tensile strength and low cost, steel is used in buildings, infrastructure, tools, ships, trains, cars, machines, electrical appliances, weapons, and rockets. Iron is the base metal of steel. Depending on the temperature, it can take two crystalline forms (allotropic forms): body-centred cubic and face-centred cubic. The interaction of the allotropes of iron with the alloying elements, primarily carbon, gives steel and cast iron their range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile, or soft and easily formed. In steel, small amounts of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for limes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuff
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock containing 25% to 75% ash is described as tuffaceous (for example, ''tuffaceous sandstone''). Tuff composed of sandy volcanic material can be referred to as volcanic sandstone. Tuff is a relatively soft rock, so it has been used for construction since ancient times. Because it is common in Italy, the Romans used it often for construction. The Rapa Nui people used it to make most of the ''moai'' statues on Easter Island. Tuff can be classified as either igneous or sedimentary rock. It is usually studied in the context of igneous petrology, although it is sometimes described using sedimentological terms. Tuff is often erroneously called tufa in guidebooks and in television programmes. Volcanic ash The material that is expelled in a vol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venus Of Berekhat Ram
The Venus of Berekhat Ram (280,000-250,000 BP) is a pebble found at Berekhat Ram on the Golan Heights. The pebble was modified by early humans and is suggested to represent a female human figure. Description The object was excavated and first described by Naama Goren-Inbar from the Institute of Archaeology, The Hebrew University of Jerusalem. The artifact is a scoria pebble, 35 mm long, 25 mm wide, and 21 mm thick. It weighs approximately 10 g. It was excavated in 1981 at the Acheulian site of Berekhat Ram, Golan Heights. The object is dated 280,000-250,000 BP. Goren-Inbar reported several artificial grooves on the object: one is a transversal groove in the upper third, others are longitudinal grooves on the sides below the traversal groove. Alexander Marshack performed a microscopic study of the object in 1997. He also reported artificial modifications including the transversal and longitudinal grooves found by Goren-Inbar. Finally, Francesco d'Errico and April Nowell re-exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venus Figurines
A Venus figurine is any Upper Palaeolithic statuette portraying a woman, usually carved in the round.Fagan, Brian M., Beck, Charlotte, "Venus Figurines", ''The Oxford Companion to Archaeology'', 1996, Oxford University Press, pp. 740–741 Most have been unearthed in Europe, but others have been found as far away as Siberia, and distributed across much of Eurasia. Most date from the Gravettian period (26,000–21,000 years ago). However, findings are not limited to this period; for example, the Venus of Hohle Fels dates back at least 35,000 years to the Aurignacian era, and the Venus of Monruz dates back about 11,000 years to the Magdalenian. Such figurines were carved from soft stone (such as steatite, calcite or limestone), bone or ivory, or formed of clay and fired. The latter are among the oldest ceramics known to historians. In total, over 200 such figurines are known; virtually all of modest size, between about in height.Fagan, 740 These figurines are recognised as so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petroglyphs
A petroglyph is an image created by removing part of a rock surface by incising, picking, carving, or abrading, as a form of rock art. Outside North America, scholars often use terms such as "carving", "engraving", or other descriptions of the technique to refer to such images. Petroglyphs are found worldwide, and are often associated with prehistoric peoples. The word comes from the Greek prefix , from meaning "stone", and meaning "carve", and was originally coined in French as . Another form of petroglyph, normally found in literate cultures, a rock relief or rock-cut relief is a relief sculpture carved on "living rock" such as a cliff, rather than a detached piece of stone. While these relief carvings are a category of rock art, sometimes found in conjunction with rock-cut architecture, they tend to be omitted in most works on rock art, which concentrate on engravings and paintings by prehistoric or nonliterate cultures. Some of these reliefs exploit the rock's na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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