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Jade Use In Mesoamerica
Jade use in Mesoamerica for symbolic and ideological ritual was highly influenced by its rarity and value among pre-Columbian Mesoamerican cultures, such as the Olmec, the Maya, and the various groups in the Valley of Mexico. Although jade artifacts have been created and prized by many Mesoamerican peoples, the Motagua River valley in Guatemala was previously thought to be the sole source of jadeite in the region. This extreme durability makes fine grained or fibrous jadeite and nephrite highly useful for Mesoamerican technology. It was often worked or carved as ornamental stones, a medium upon which glyphs were inscribed, or shaped into figurines, weapons, and other objects. Many jade artifacts crafted by later Mesoamerican civilizations appear cut from simple jade axes, implying that the earliest jadeite trade was based in utilitarian function. Jade and jadeite In general terms, jade refers to two distinct minerals: nephrite, a calcium- and magnesium-rich amphibole minera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maya Jade Plaque
Maya may refer to: Ethnic groups * Maya peoples, of southern Mexico and northern Central America ** Maya civilization, the historical civilization of the Maya peoples ** Mayan languages, the languages of the Maya peoples * Maya (East Africa), a population native to the old Wej province in Ethiopia * Sibuyanon, a Visayan population sometimes "May-" native to Sibuyan Island in the Philippines Religion and mythology * Maya (religion), in Indian religions, relates to the illusion of reality *Maya (mother of the Buddha) (died 563 BC), mother of the historical Buddha *Mayasura or Maya, a Hindu demon * Maya religion, the religious practices of the Maya peoples of parts of Mexico and Central America ** Maya mythology, the myths and legends of the Maya civilization People * Maya (given name), a feminine name (including a list of people and fictional characters with the name) Places * Maya (Aldan), a river in Yakutia and the north of Khabarovsk Krai, Russia * Maya (Uda), a river in Amur O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephrite
Nephrite is a variety of the calcium, magnesium, and iron-rich amphibole minerals tremolite or actinolite ( aggregates of which also make up one form of asbestos). The chemical formula for nephrite is Ca2( Mg, Fe)5 Si8 O22(O H)2. It is one of two different mineral species called jade. The other mineral species known as jade is jadeite, which is a variety of pyroxene. While nephrite jade possesses mainly grays and greens (and occasionally yellows, browns, black or whites), jadeite jade, which is rarer, can also contain blacks, reds, pinks and violets. Nephrite jade is an ornamental stone used in carvings, beads, or cabochon cut gemstones. Nephrite is also the official state mineral of Wyoming. Nephrite can be found in a translucent white to very light yellow form which is known in China as ''mutton fat'' jade, in an opaque white to very light brown or gray which is known as ''chicken bone'' jade, as well as in a variety of green colors. Western Canada is the principal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trace Element
__NOTOC__ A trace element is a chemical element of a minute quantity, a trace amount, especially used in referring to a micronutrient, but is also used to refer to minor elements in the composition of a rock, or other chemical substance. In nutrition, trace elements are classified into two groups: essential trace elements, and non-essential trace elements. Essential trace elements are needed for many physiological and biochemical processes in both plants and animals. Not only do trace elements play a role in biological processes but they also serve as catalysts to engage in redox – oxidation and reduction mechanisms. Trace elements of some heavy metals have a biological role as essential micronutrients. Types The two types of trace element in biochemistry are classed as essential or non-essential. Essential trace elements An essential trace element is a dietary element, a mineral that is only needed in minute quantities for the proper growth, development, and physiology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartzite
Quartzite is a hard, non- foliated metamorphic rock that was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts, and hence quartzite is a metasandstone. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysoprase
Chrysoprase, chrysophrase or chrysoprasus is a gemstone variety of chalcedony (a cryptocrystalline form of silica) that contains small quantities of nickel. Its color is normally apple-green, but varies from turquoise-like cyan to deep green. The darker varieties of chrysoprase are also referred to as prase. (However, the term prase is also used to describe chlorite-included quartz, and to a certain extent is a color-descriptor, rather than a rigorously defined mineral variety.) Chrysoprase is cryptocrystalline, which means that it is composed of crystals so fine that they cannot be seen as distinct particles under normal magnification. This sets it apart from rock crystal, amethyst, citrine, and the other varieties of crystalline quartz. Other members of the cryptocrystalline silica family include agate, carnelian, and onyx. Unlike many non-transparent silica minerals, it is the color of chrysoprase, rather than any pattern of markings, that makes it desirable. The word chryso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omphacite
Omphacite is a member of the clinopyroxene group of silicate minerals with formula: ( Ca, Na)( Mg, Fe2+, Al) Si2 O6. It is a variably deep to pale green or nearly colorless variety of clinopyroxene. It normally appears in eclogite, which is the high-pressure metamorphic rock of basalt. Omphacite is the solid solution of Fe-bearing diopside and jadeite. It crystallizes in the monoclinic system with prismatic, typically twinned forms, though usually anhedral. Its space group can be P2/n or C2/c depending on the thermal history. It exhibits the typical near 90° pyroxene cleavage. It is brittle with specific gravity of 3.29 to 3.39 and a Mohs hardness of 5 to 6. Formation and occurrence Omphacite is the dominated phase in the subducted oceanic crust in the Earth's upper mantle. The Mid-Ocean Ridge Basalt, which makes up oceanic crust, goes through ultrahigh-pressure metamorphic process and transforms to eclogite at depth ~60 km in the subduction zones. The major mineral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albite
Albite is a plagioclase feldspar mineral. It is the sodium endmember of the plagioclase solid solution series. It represents a plagioclase with less than 10% anorthite content. The pure albite endmember has the formula . It is a tectosilicate. Its color is usually pure white, hence its name from Latin, . It is a common constituent in felsic rocks. Properties Albite crystallizes with triclinic pinacoidal forms. Its specific gravity is about 2.62 and it has a Mohs hardness of 6 to 6.5. Albite almost always exhibits crystal twinning often as minute parallel striations on the crystal face. Albite often occurs as fine parallel segregations alternating with pink microcline in perthite as a result of exolution on cooling. There are two variants of albite, which are referred to as 'low albite' and 'high albite'; the latter is also known as 'analbite'. Although both variants are triclinic, they differ in the volume of their unit cell, which is slightly larger for the 'high' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminum
Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has a great affinity towards oxygen, passivation (chemistry), forming a protective layer of aluminium oxide, oxide on the surface when exposed to air. It visually resembles silver, both in its color and in its great ability to reflect light. It is soft, magnetism, nonmagnetic, and ductility, ductile. It has one stable isotope, 27Al, which is highly abundant, making aluminium the abundance of the chemical elements, 12th-most abundant element in the universe. The radioactive decay, radioactivity of aluminium-26, 26Al leads to it being used in radiometric dating. Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium
Sodium is a chemical element; it has Symbol (chemistry), symbol Na (from Neo-Latin ) and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 element, group 1 of the periodic table. Its only stable isotope is 23Na. The free metal does not occur in nature and must be prepared from compounds. Sodium is the Abundance of elements in Earth's crust, sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been Leaching (chemistry), leached by the action of water from the Earth, Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans. Sodium was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide. Among many other useful sodium compounds, sodium hydroxide (lye) is used in Soap, soap manufac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroxene
The pyroxenes (commonly abbreviated Px) are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. Pyroxenes have the general formula , where X represents ions of calcium (Ca), sodium (Na), iron (Fe(II)) or magnesium (Mg) and more rarely zinc, manganese or lithium, and Y represents ions of smaller size, such as chromium (Cr), aluminium (Al), magnesium (Mg), cobalt (Co), manganese (Mn), scandium (Sc), titanium (Ti), vanadium (V) or even iron (Fe(II) or Fe(III)). Although aluminium substitutes extensively for silicon in silicates such as feldspars and amphiboles, the substitution occurs only to a limited extent in most pyroxenes. They share a common structure consisting of single chains of silica tetrahedra. Pyroxenes that crystallize in the monoclinic system are known as clinopyroxenes and those that crystallize in the orthorhombic system are known as orthopyroxenes. The name ''pyroxene'' is derived from the Ancient Greek w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jadeite
Jadeite is a pyroxene mineral with composition Na Al Si2 O6. It is hard (Mohs hardness of about 6.5 to 7.0), very tough, and dense, with a specific gravity of about 3.4. It is found in a wide range of colors, but is most often found in shades of green or white. Jadeite is formed only in the subduction zones of continental margins, where rock undergoes metamorphism at high pressure but relatively low temperature. Jadeite is the principal mineral making up the most valuable form of jade, a precious stone particularly prized in China. Most gem-quality jadeite jade comes from northern Myanmar. Jade tools and implements have been found at Stone Age sites, showing that the mineral has been prized by humans since before the beginning of recorded history, written history. Name The name ''jadeite'' is derived (via and ) from the Spanish language, Spanish phrase "piedra de ijada" which means "stone of the side". The Latin version of the name, ''lapis nephriticus'', is the origin of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Minerals'; p. 1. In the series ''Geology: Landforms, Minerals, and Rocks''. Rosen Publishing Group. The Geology, geological definition of mineral normally excludes compounds that occur only in living organisms. However, some minerals are often biogenic (such as calcite) or organic compounds in the sense of chemistry (such as mellite). Moreover, living organisms often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks. The concept of mineral is distinct from rock (geology), rock, which is any bulk solid geologic material that is relatively homogeneous at a large enough scale. A rock may consist of one type of mineral or may be an aggregate (geology), aggregate of two or more different types of minerals, spaci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
