Oregon
Oregon is a state in the Pacific Northwest region on the West Coast of the United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho; the parallel 42 ° north delineates the southern boundary with Nevada. Oregon is one of only four states of the continental United States to have a coastline on the Pacific Ocean. Oregon was inhabited by many indigenous tribes before Western traders and settlers arrived. An autonomous government was formed in the Oregon Country in 1843 before the Oregon Territory was created in 1848. Oregon became the 33rd state on February 14, 1859. Today, at 98,000 square miles, Oregon is the ninth largest and, with a population of 4 million, 27th most populous U. S. state. The capital, Salem, is the second most populous city in Oregon, with 169,798 residents. Portland, with 647,805, ranks as the 26th among U. S. cities. The Portland metropolitan area, which includes the city of Vancouver, Washington, to the north, ranks the 25th largest metro area in the nation, with a population of 2,453,168.
Oregon is one of the most geographically diverse states in the U. S. marked by volcanoes, abundant bodies of water, dense evergreen and mixed forests, as well as high deserts and semi-arid shrublands. At 11,249 feet, Mount Hood, a stratovolcano, is the state's highest point. Oregon's only national park, Crater Lake National Park, comprises the caldera surrounding Crater Lake, the deepest lake in the United States; the state is home to the single largest organism in the world, Armillaria ostoyae, a fungus that runs beneath 2,200 acres of the Malheur National Forest. Because of its diverse landscapes and waterways, Oregon's economy is powered by various forms of agriculture and hydroelectric power. Oregon is the top timber producer of the contiguous United States, the timber industry dominated the state's economy in the 20th century. Technology is another one of Oregon's major economic forces, beginning in the 1970s with the establishment of the Silicon Forest and the expansion of Tektronix and Intel.
Sportswear company Nike, Inc. headquartered in Beaverton, is the state's largest public corporation with an annual revenue of $30.6 billion. The earliest evidence of the name Oregon has Spanish origins; the term "orejón" comes from the historical chronicle Relación de la Alta y Baja California written by the new Spaniard Rodrigo Montezuma and made reference to the Columbia River when the Spanish explorers penetrated into the actual North American territory that became part of the Viceroyalty of New Spain. This chronicle is the first topographical and linguistic source with respect to the place name Oregon. There are two other sources with Spanish origins, such as the name Oregano, which grows in the southern part of the region, it is most probable that the American territory was named by the Spaniards, as there are some populations in Spain such as "Arroyo del Oregón" considering that the individualization in Spanish language "El Orejón" with the mutation of the letter "g" instead of "j". Another early use of the name, spelled Ouragon, was in a 1765 petition by Major Robert Rogers to the Kingdom of Great Britain.
The term referred to the then-mythical River of the West. By 1778, the spelling had shifted to Oregon. In his 1765 petition, Rogers wrote: The rout...is from the Great Lakes towards the Head of the Mississippi, from thence to the River called by the Indians Ouragon... One theory is that the name comes from the French word ouragan, applied to the River of the West based on Native American tales of powerful Chinook winds on the lower Columbia River, or from firsthand French experience with the Chinook winds of the Great Plains. At the time, the River of the West was thought to rise in western Minnesota and flow west through the Great Plains. Joaquin Miller explained in Sunset magazine, in 1904, how Oregon's name was derived: The name, Oregon, is rounded down phonetically, from Ouve água—Oragua, Or-a-gon, Oregon—given by the same Portuguese navigator that named the Farallones after his first officer, it in a large way, means cascades:'Hear the waters.' You should steam up the Columbia and hear and feel the waters falling out of the clouds of Mount Hood to understand the full meaning of the name Ouve a água, Oregon.
Another account, endorsed as the "most plausible explanation" in the book Oregon Geographic Names, was advanced by George R. Stewart in a 1944 article in American Speech. According to Stewart, the name came from an engraver's error in a French map published in the early 18th century, on which the Ouisiconsink River was spelled "Ouaricon-sint", broken on two lines with the -sint below, so there appeared to be a river flowing to the west named "Ouaricon". According to the Oregon Tourism Commission, present-day Oregonians pronounce the state's name as "or-uh-gun, never or-ee-gone". After being drafted by the Detroit Lions in 2002, former Oregon Ducks quarterback Joey Harrington distributed "Orygun" stickers to members of the media as a reminder of how to pronounce the name of his home state; the stickers are sold by the University of Oregon Bookstore. Oregon is 295 miles north to south at longest distance, 395 miles east to west. With an area of 98,381 square miles, Oregon is larger than the United Kingdom.
It is the ninth largest state in the United States. Oregon's highest point is the summit of Mount Hood, at 11,249 feet, its lowest point is the sea level of the Pacific Ocean along the Oregon Coas
Pacific Coast Ranges
The Pacific Coast Ranges, are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico. The Pacific Coast Ranges are part of the North American Cordillera, which includes the Rocky Mountains, Columbia Mountains, Interior Mountains, the Interior Plateau, Sierra Nevada Mountains, the Great Basin mountain ranges, other ranges and various plateaus and basins; the Pacific Coast Ranges designation, only applies to the Western System of the Western Cordillera, which comprises the Saint Elias Mountains, Coast Mountains, Insular Mountains, Olympic Mountains, Cascade Range, Oregon Coast Range, California Coast Ranges, Transverse Ranges, Peninsular Ranges, the Sierra Madre Occidental. The term Coast Range is not used by the United States Geological Survey to refer only to the ranges east from the Strait of Juan de Fuca in Washington to the California-Mexico border. I.e. the Pacific Border province. The same term is used informally in Canada to refer to the Coast Mountains and adjoining inland ranges such as the Hazelton Mountains, sometimes the Saint Elias Mountains.
The character of the ranges varies from the record-setting tidewater glaciers in the ranges of Alaska, to the rugged Central and Southern California ranges, the Transverse Ranges and Peninsular Ranges, in the chaparral and woodlands ecoregion with Oak Woodland, Chaparral shrub forest or Coastal sage scrub-covering them. The coastline is dropping steeply into the sea with photogenic views. Along the British Columbia and Alaska coast, the mountains intermix with the sea in a complex maze of fjords, with thousands of islands. Off the Southern California coast the Channel Islands archipelago of the Santa Monica Mountains extends for 160 miles. There are coastal plains at the mouths of rivers that have punched through the mountains spreading sediments, most notably at the Copper River in Alaska, the Fraser River in British Columbia, the Columbia River between Washington and Oregon. In California: the Sacramento and San Joaquin Rivers' San Francisco Bay, the Santa Clara River's Oxnard Plain, the Los Angeles, San Gabriel, Santa Ana Rivers' Los Angeles Basin - a coastal sediment-filled plain between the peninsular and transverse ranges with sediment in the basin up to 6 miles deep, the San Diego River's Mission Bay.
From the vicinity of San Francisco Bay north, it is common in winter for cool unstable air masses from the Gulf of Alaska to make landfall in one of the Coast Ranges, resulting in heavy precipitation, both as rain and snow on their western slopes. The same Winter weather occurs with less frequency and precipitation in Southern California, with the mountains' western faces and peaks causing an eastward rainshadow that produces the arid desert regions. Omitted from the list below, but included is the Sierra Nevada, a major mountain range of eastern California, separated by the Central Valley over much of its length from the California Coast Ranges and the Transverse Ranges. On the West coast of North America, the coast ranges and the coastal plain form the margin. Most of the land is made of terranes. In the north, the insular belt is an accreted terrane; this belt extends from the Wrangellia Terrane in Alaska to the Chilliwack group of Canada. A rupture in Rodinia 750 million years ago formed a passive margin in the eastern Pacific Northwest.
The breakup of Pangea 200 million years ago began the westward movement of the North American plate, creating an active margin on the western continent. As the continent drifted West, terranes were accreted onto the west coast; the timing of the accretion of the insular belt is uncertain, although the closure did not occur until at least 115 million years ago. Other Mesozoic terranes that accreted onto the continent include the Klamath Mountains, the Sierra Nevada, the Guerrero super-terrane of western Mexico. 80 to 90 million years ago the subducting Farallon plate split and formed the Kula Plate to the North. This formed an area in what is now Northern California, where the plates converged forming a Mélange. North of this was the Columbia Embayment, where the continental margin was east of the surrounding areas. Many of the major batholiths date from the late Cretaceous; as the Laramide Orogeny ended around 48 million years ago, the accretion of the Siletzia terrane began in the Pacific Northwest.
This began the volcanic activity in the Cascadia subduction zone, forming the modern Cascade Range, lasted into the Miocene. Events here may relate to the ignimbrite flare-up of Range; as extension in the Basin and Range Province slowed by a change in North American Plate movement circa 7 to 8 Million years ago, rifting began on the Gulf of California. Although many of the ranges do share a common geologic history, the Pacific Coast Ranges province is not defined by geology, but rather by geography. Many of the various ranges are composed of distinct forms of rock from many different periods of geological time from the Precambrian in parts of the Little San Bernardino Mountains to 10,000-year-old rock in the Cascade Range. For one example, the Peninsular Ranges, composed of Mesozoic batholitic rock, are geologically extr
Crescent City, California
Crescent City is the county seat of, only incorporated city in, Del Norte County, California. Named for the crescent-shaped stretch of sandy beach south of the city, Crescent City had a total population of 7,643 in the 2010 census, up from 4,006 in the 2000 census; the population includes inmates at Pelican Bay State Prison within the city limits, the former census-designated place Crescent City North annexed to the city. The city is the site of the Redwood National Park headquarters, as well as the historic Battery Point Light. Due to the richness of the local Pacific Ocean waters and the related catch, ease of access, Crescent City Harbor serves as home port for numerous commercial fishing vessels; the city is located on the Pacific coast in the upper northwestern part of California, about 20 miles south of the Oregon border. Crescent City's offshore geography makes it unusually susceptible to tsunamis. Much of the city was destroyed by four tsunami waves generated by the Good Friday earthquake off Anchorage, Alaska in 1964.
More the city's harbor suffered extensive damage and destruction due to tsunamis generated by the March 11, 2011 earthquake off Sendai, Japan. Several dozen vessels and many of the docks they were moored to were destroyed as wave cycles related to the tsunamis exceeded 8 feet, its climate is very moderate, with cool summers for its latitude as a result of intense maritime moderation. Nearby inland areas behind the mountains have warmer summers; the area, now known as Del Norte County was and still is inhabited by the Yurok and Tolowa Nations of indigenous peoples. The first European American to explore this land was pioneer Jedediah Smith in the early 19th century, he was the first European American to reach the area overland on foot in a time before the European Americans knew anything about such a distant territory. For him it was "Land's End" — where the American continent ended at the Pacific Ocean. In 1855 Congress authorized the building of a lighthouse at "the battery point", still functioning as a historical landmark.
European explorers first visited the area now known as Crescent City by ship in the late-1820s. Europeans began moving to the area in the 1850s. Crescent City was incorporated as a city in 1854. Crescent City was the name of a 113-ton schooner built in 1848 by Joshua T. Foster of Medford, MA; the Brother Jonathan, a paddle steamer, crashed on an uncharted rock near Point St. George, off the coast of Crescent City, California, on 30 July 1865. A 1906 ship named Crescent City was the former Jim Butler, a 701-ton steam schooner built by Lindstrom Shipbuilding Company in Aberdeen, that wrecked in the Channel Islands, off Santa Cruz Island, in 1927; the SS Emidio was a 6912-ton tanker of the General Petroleum Corporation, which became the first casualty of the Imperial Japanese Navy's submarine force action on California's Pacific Coast. The abandoned tanker broke up on the rocks off Crescent City; the remaining pieces of the ship are now California Historical Landmark #497. According to the United States Census Bureau, the city has a total area of 2.415 square miles, of which 1.963 square miles is land and 0.452 square miles is water.
Fishing and crabbing and timber are the major sources of income in the city, as well as the County of Del Norte. The mouth of Elk Creek, where it flows into the Pacific Ocean, is in Crescent City, its nearest Californian place of any size to its interior is Happy Camp separated by 42 miles by air, but due to the unsuitable terrain it is much farther away by road. The nearest city is fellow coastal city Brookings, around 20 miles to its north; the Humboldt Bay area encompassing Eureka and Arcata is more than 60 miles to its south. Crescent City is as far north in latitude as Chicago as well as New England on the Atlantic side and is as much as nine degrees latitude north of San Diego at the southern tip of the state. Crescent City has a cool-summer mediterranean climate, with moderation similar to an oceanic climate, it is one of the wettest places in California: the annual rainfall is 71.24 inches or 1,810 millimetres. The wettest months are from October to March; the average high and low temperatures in January are 54 °F or 12.2 °C and 41 °F or 5 °C.
The average high and low temperatures in August are 66 °F or 18.9 °C and 51 °F or 11 °C. On average, fifteen mornings each winter fall below 32 °F or 0 °C; the highest temperature recorded in Crescent City was 93 °F, observed on September 24, 1964, June 1, 1970, October 10, 1991. The lowest temperature on record was 19 °F on December 21, 1990; the maximum monthly precipitation was 31.25 inches in November 1973, while the wettest “rain year” has been from July 1937 to June 1938 when 107.74 inches fell, the driest certainly that from July 1976 to June 1977 with less than 40 inches. The maximum 24-hour precipitation was 7.73 inches on January 9, 1995. The highest snowfall recorded for any period in 24 hours was 6.0 inches occurring on January 6, 1972. The topography of the sea floor surrounding Crescent City has the effect of focusing tsunamis. According to researchers at Humboldt State University and the University of Southern California, the city experienced tsunami conditions 31 times between the years 1933 and 2008.
Although many
Trinity County, California
Trinity County is a county in the northwestern part of the state of California. As of the 2010 census, the population was 13,786, making it the fourth least-populous county in California; the county seat and largest community is Weaverville. Weaverville has the distinction of housing some of California's oldest buildings; the courthouse, built in 1856, is the second oldest in the state, the Weaverville Drug Store has been filling prescriptions since 1852. The Joss House is a historic Taoist temple built in 1873. Trinity County is rugged, mountainous forested, lies along the Trinity River within the Salmon and Klamath Mountains, it is one of three counties in California with no incorporated cities. The county takes its name from the Trinity River, named in 1845 by Major Pierson B. Reading, under the mistaken impression that the river emptied into Trinidad Bay. Trinity is the English translation of Trinidad. Trinity County was one of the original counties of California, created in 1850 at the time of statehood.
Parts of the county were given to Klamath County in 1852 and to Humboldt County in 1853. According to the U. S. Census Bureau, the county has a total area of 3,208 square miles, of which 3,179 square miles is land and 28 square miles is water; the county contains a significant portion of Shasta-Trinity National Forest, home to the Trinity Alps. The county hosts many visitors during summer months, for camping, boating on the lakes, rafting/kayaking on the rivers and fishing; the summers tend to be clear, sunny and dry, with little rain from June to September except for some mountain thunderstorms in the highest elevations. The winters tend to have copious precipitation, falling as rain under 1000m/3300 ft in the valley bottoms, as snow over 1000m/3300 ft on the mountainsides. December and February are the wettest. There is an extensive wild river and stream system, the terrain is quite rugged and forested, with the highest point at Mount Eddy, over 9,000 ft; the Klamath Mountains occupy the vast portion of the county.
Siskiyou County - north Shasta County - east Tehama County - southeast Mendocino County - south Humboldt County - west Shasta-Trinity National Forest Six Rivers National Forest Mendocino National Forest Shasta-Trinity National Recreation Area Trinity Alps Wilderness Yolla Bolly-Middle Eel Wilderness Trinity was a Republican-leaning county in Presidential and congressional elections until recently. No Democrat had won the county since Jimmy Carter in 1976 until Barack Obama defeated John McCain by a 4% margin in 2008. In 2012, the county narrowly. Voter registration reflects this trend, with Democratic and Republican registration in a near dead heat. Third-party candidates tend to do rather well in Trinity County: George Wallace got over 13% of the county's vote in 1968, it was the only California county carried by Ross Perot in 1992, it was Perot's best performance in the state in 1996, although he didn't carry it again. John Anderson did well in 1980, as did third-party candidates in 2016. Trinity County is in California's 2nd congressional district, represented by Democrat Jared Huffman.
In the state legislature Trinity is in the 2nd Senate District, represented by Democrat Mike McGuire, the 2nd Assembly District, represented by Democrat Jim Wood. In 2010, Trinity County voted against Proposition 19, which would have taxed and regulated marijuana. In 2016 Trinity County residents were asked again to vote on legalization of state-level recreational marijuana, facilitated by the Adult Use of Marijuana Act known as California Proposition 64; the measure passed with 50.1% in favor of legalization. Statewide, the measure passed with 57.1% of the vote. State Route 299 State Route 3 State Route 36 Trinity Transit provides weekday intercity bus service on State Routes 3 and 299, with connecting service in Willow Creek and Redding. Service is provided from Weaverville to Lewiston and Hayfork; the county owns five general aviation airports: Trinity Center Airport, Weaverville Airport, Hayfork Airport, Hyampom Airport and Ruth Airport. The following table includes the number of incidents reported and the rate per 1,000 persons for each type of offense.
The 2010 United States Census reported that Trinity County had a population of 13,786. The racial makeup of Trinity County was 12,033 White, 59 African American, 655 Native American, 94 Asian, 16 Pacific Islander, 217 from other races, 712 from two or more races. Hispanic or Latino of any race were 959 persons; as of the census of 2000, there were 13,022 people, 5,587 households, 3,625 families residing in the county. The population density was 4 people per square mile. There were 7,980 housing units at an average density of 2 per square mile; the racial makeup of the county was 88.9% White, 0.5% Black or African American, 4.9% Native American, 0.5% Asian, 0.1% Pacific Islander, 0.9% from other races, 4.4% from two or more races. 4.0% of the population were Hispanic or Latino of any race. 16.1% were of German, 13.4% English, 12.1% Irish and 9.5% American ancestry according to Census 2000. 97.3% spoke English and 1.8% Spanish as their first language. There were 5,587 households out of which 25.4% had children under the age of 18 living with them, 50.5% were married couples living together, 10.1% had a female householder with no husband present, 35.1% were non-families.
29.5% of all households were made up of individuals and 11.1% had someone living alone, 65 years of age or older. The average hou
United States National Forest
National Forest is a classification of protected and managed federal lands in the United States. National Forests are forest and woodland areas owned collectively by the American people through the federal government, managed by the United States Forest Service, a division of the United States Department of Agriculture; the National Forest System was created by the Land Revision Act of 1891, signed under the presidency of Benjamin Harrison. It was the result of concerted action by Los Angeles-area businessmen and property owners who were concerned by the harm being done to the watershed of the San Gabriel Mountains by ranchers and miners. Abbot Kinney and forester Theodore Lukens were key spokesmen for the effort. In the United States there are 155 National Forests containing 190 million acres of land; these lands comprise 8.5 percent of the total land area of the United States, an area about the size of Texas. Some 87 percent of National Forest land lies west of the Mississippi River in the mountain ranges of the Western United States.
Alaska has 12 percent of all National Forest lands. The U. S. Forest Service manages all of the United States National Grasslands, around half of the United States National Recreation Areas. There are two distinctly different types of forests within the National Forest system; those east of the Great Plains in the Midwestern and Eastern United States were acquired by the federal government since 1891, may be second growth forests. The land had long been in the private domain and sometimes logged since colonial times, but was purchased by the United States government in order to create new National Forests; those west of the Great Plains in the Western United States, though established since 1891, are on lands with ownership maintained by the federal government since the U. S. acquisition and settling of the American West. These are lands that were kept in the public domain, with the exception of inholdings and donated or exchanged private forest lands. Land management of these areas focuses on conservation, timber harvesting, livestock grazing, watershed protection and recreation.
Unlike national parks and other federal lands managed by the National Park Service, extraction of natural resources from national forests is permitted, in many cases encouraged. However, the first-designated wilderness areas, some of the largest, are on National Forest lands. There are management decision conflicts between conservationists and environmentalists, natural resource extraction companies and lobbies, over the protection and/or use of National Forest lands; these conflicts center on endangered species protection, logging of old-growth forests, intensive clear cut logging, undervalued stumpage fees, mining operations and mining claim laws, logging/mining access road-building within National Forests. Additional conflicts arise from concerns that the grasslands and forest understory are grazed by sheep, and, more rising numbers of elk and mule deer due to loss of predators. Many ski resorts and summer resorts operate on leased land in National Forests. List of U. S. National Forests United States National Grassland National Forests of the United States topics State forest National Forest Management Act of 1976 Protected areas of the United States USDA Forest Service USDA Forest Service - The First Century 100 Years of Federal Forestry
Serpentine subgroup
The serpentine subgroup are greenish, brownish, or spotted minerals found in serpentinite rocks. They are used as a source of magnesium and asbestos, as a decorative stone; the name is thought to come from the greenish color being that of a serpent. The serpentine group describes a group of common rock-forming hydrous magnesium iron phyllosilicate minerals, resulting from the metamorphism of the minerals that are contained in ultramafic rocks, they may contain minor amounts of other elements including chromium, cobalt or nickel. In mineralogy and gemology, serpentine may refer to any of 20 varieties belonging to the serpentine group. Owing to admixture, these varieties are not always easy to individualize, distinctions are not made. There are three important mineral polymorphs of serpentine: antigorite and lizardite; the serpentine group of minerals are polymorphous, meaning that they have the same chemical formulae, but the atoms are arranged into different structures, or crystal lattices. Chrysotile, which has a fiberous habit, is one polymorph of serpentine and is one of the more important asbestos minerals.
Other polymorphs in the serpentine group may have a platy habit. Antigorite and lizardite are the polymorphs with platy habit. Many types of serpentine have been used for jewellery and hardstone carving, sometimes under the name false jade or Teton jade, their olive green colour and smooth or scaly appearance is the basis of the name from the Latin serpentinus, meaning "serpent rock," according to Best. They have their origins in metamorphic alterations of pyroxene. Serpentines may pseudomorphously replace other magnesium silicates. Alterations may be incomplete. Where they form a significant part of the land surface, the soil is unusually high in clay. Antigorite is the polymorph of serpentine that most forms during metamorphism of wet ultramafic rocks and is stable at the highest temperatures—to over 600 °C at depths of 60 km or so. In contrast and chrysotile form near the Earth's surface and break down at low temperatures well below 400 °C, it has been suggested that chrysotile is never stable relative to either of the other two serpentine polymorphs.
Samples of the oceanic crust and uppermost mantle from ocean basins document that ultramafic rocks there contain abundant serpentine. Antigorite contains water in about 13 percent by weight. Hence, antigorite may play an important role in the transport of water into the earth in subduction zones and in the subsequent release of water to create magmas in island arcs, some of the water may be carried to yet greater depths. Soils derived from serpentine are toxic to many plants, because of high levels of nickel and cobalt; the flora is very distinctive, with specialised, slow-growing species. Areas of serpentine-derived soil will show as strips of shrubland and open, scattered small trees within otherwise forested areas. Most serpentines are opaque to translucent, soft and susceptible to acids. All are massive in habit, never being found as single crystals. Lustre may be greasy or silky. Colours range from white to grey, yellow to green, brown to black, are splotchy or veined. Many are intergrown such as calcite and dolomite.
Occurrence is worldwide. Serpentines find use in industry for a number of purposes, such as railway ballasts, building materials, the asbestiform types find use as thermal and electrical insulation; the asbestos content can be released to the air when serpentine is excavated and if it is used as a road surface, forming a long term health hazard by breathing. Asbestos from serpentine can appear at low levels in water supplies through normal weathering processes, but there is as yet no identified health hazard associated with use or ingestion. In its natural state, some forms of serpentine react with carbon dioxide and re-release oxygen into the atmosphere; the more attractive and durable varieties are termed "noble" or "precious" serpentine and are used extensively as gems and in ornamental carvings. The town of Bhera in the historic Punjab province of the Indian subcontinent was known for centuries for finishing a pure form of green serpentine obtained from quarries in Afghanistan into lapidary work, ornamental sword hilts, dagger handles.
This high-grade serpentine ore was known as sang-i-yashm or to the English, false jade, was used for generations by Indian craftsmen for lapidary work. It is carved, taking a good polish, is said to have a pleasingly greasy feel. Less valuable serpentine ores of varying hardness and clarity are sometimes dyed to imitate jade. Misleading synonyms for this material include "Suzhou jade", "Styrian jade", "New jade". New Caledonian serpentine is rich in nickel; the Māori of New Zealand once carved beautiful objects from local serpentine, which they c
Marble
Marble is a metamorphic rock composed of recrystallized carbonate minerals, most calcite or dolomite. Marble is not foliated, although there are exceptions. In geology, the term "marble" refers to metamorphosed limestone, but its use in stonemasonry more broadly encompasses unmetamorphosed limestone. Marble is used for sculpture and as a building material; the word "marble" derives from the Ancient Greek μάρμαρον, from μάρμαρος, "crystalline rock, shining stone" from the verb μαρμαίρω, "to flash, gleam". This stem is the ancestor of the English word "marmoreal", meaning "marble-like." While the English term "marble" resembles the French marbre, most other European languages, more resemble the original Ancient Greek. Marble is a rock resulting from metamorphism of sedimentary carbonate rocks, most limestone or dolomite rock. Metamorphism causes variable recrystallization of the original carbonate mineral grains; the resulting marble rock is composed of an interlocking mosaic of carbonate crystals.
Primary sedimentary textures and structures of the original carbonate rock have been modified or destroyed. Pure white marble is the result of metamorphism of a pure limestone or dolomite protolith; the characteristic swirls and veins of many colored marble varieties are due to various mineral impurities such as clay, sand, iron oxides, or chert which were present as grains or layers in the limestone. Green coloration is due to serpentine resulting from magnesium-rich limestone or dolostone with silica impurities; these various impurities have been mobilized and recrystallized by the intense pressure and heat of the metamorphism. Examples of notable marble varieties and locations: White marble has been prized for its use in sculptures since classical times; this preference has to do with its softness, which made it easier to carve, relative isotropy and homogeneity, a relative resistance to shattering. The low index of refraction of calcite allows light to penetrate several millimeters into the stone before being scattered out, resulting in the characteristic waxy look which gives "life" to marble sculptures of any kind, why many sculptors preferred and still prefer marble for sculpting.
Construction marble is a stone, composed of calcite, dolomite or serpentine, capable of taking a polish. More in construction the dimension stone trade, the term "marble" is used for any crystalline calcitic rock useful as building stone. For example, Tennessee marble is a dense granular fossiliferous gray to pink to maroon Ordovician limestone, that geologists call the Holston Formation. Ashgabat, the capital city of Turkmenistan, was recorded in the 2013 Guinness Book of Records as having the world's highest concentration of white marble buildings. According to the United States Geological Survey, U. S. domestic marble production in 2006 was 46,400 tons valued at about $18.1 million, compared to 72,300 tons valued at $18.9 million in 2005. Crushed marble production in 2006 was 11.8 million tons valued at $116 million, of which 6.5 million tons was finely ground calcium carbonate and the rest was construction aggregate. For comparison, 2005 crushed marble production was 7.76 million tons valued at $58.7 million, of which 4.8 million tons was finely ground calcium carbonate and the rest was construction aggregate.
U. S. dimension marble demand is about 1.3 million tons. The DSAN World Demand for Marble Index has shown a growth of 12% annually for the 2000–2006 period, compared to 10.5% annually for the 2000–2005 period. The largest dimension marble application is tile. In 1998, marble production was dominated by 4 countries that accounted for half of world production of marble and decorative stone. Italy and China were the world leaders, each representing 16% of world production, while Spain and India produced 9% and 8%, respectively. Italy is the world leader in marble export, with 20% share in global marble production, followed by China with 16%, India with 10%, Spain with 6%, Portugal with 5%. Dust produced by cutting marble could cause lung disease but more research needs to be carried out on whether dust filters and other safety products reduce this risk; the Occupational Safety and Health Administration has set the legal limit for marble exposure in the workplace as 15 mg/m3 total exposure and 5 mg/m3 respiratory exposure over an 8-hour workday.
The National Institute for Occupational Safety and Health has set a recommended exposure limit of 10 mg/m3 total exposure and 5 mg/m3 respiratory exposure over an 8-hour workday. Acids damage marble, because the calcium carbonate in marble reacts with them, releasing carbon dioxide: CaCO3 + 2H+ → Ca2+ + CO2 + H2O Thus, vinegar or other acidic solutions should never be used on marble. Outdoor marble statues, gravestones, or other marble structures are damaged by acid rain; the haloalkaliphilic methylotrophic bacterium Methylophaga murata was isolated from deteriorating marble in the Kremlin. Bacterial and fungal degradation was detected in four samples of marble from Milan cathedral; as the favorite medium for Greek and Roman sculptors and architects, marble has become a cultural symbol of tradition and refined taste. Its varied and colorful patterns make i
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