The mineral pyrite, or iron pyrite known as fool's gold, is an iron sulfide with the chemical formula FeS2. Pyrite is considered the most common of the sulfide minerals. Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fool's gold; the color has led to the nicknames brass and Brazil used to refer to pyrite found in coal. The name pyrite is derived from the Greek πυρίτης, "of fire" or "in fire", in turn from πύρ, "fire". In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel. By Georgius Agricola's time, c. 1550, the term had become a generic term for all of the sulfide minerals. Pyrite is found associated with other sulfides or oxides in quartz veins, sedimentary rock, metamorphic rock, as well as in coal beds and as a replacement mineral in fossils, but has been identified in the sclerites of scaly-foot gastropods. Despite being nicknamed fool's gold, pyrite is sometimes found in association with small quantities of gold.
Gold and arsenic occur as a coupled substitution in the pyrite structure. In the Carlin–type gold deposits, arsenian pyrite contains up to 0.37% gold by weight. Pyrite enjoyed brief popularity in the 16th and 17th centuries as a source of ignition in early firearms, most notably the wheellock, where a sample of pyrite was placed against a circular file to strike the sparks needed to fire the gun. Pyrite has been used since classical times to manufacture copperas. Iron pyrite was allowed to weather; the acidic runoff from the heap was boiled with iron to produce iron sulfate. In the 15th century, new methods of such leaching began to replace the burning of sulfur as a source of sulfuric acid. By the 19th century, it had become the dominant method. Pyrite remains in commercial use for the production of sulfur dioxide, for use in such applications as the paper industry, in the manufacture of sulfuric acid. Thermal decomposition of pyrite into FeS and elemental sulfur starts at 540 °C. A newer commercial use for pyrite is as the cathode material in Energizer brand non-rechargeable lithium batteries.
Pyrite is a semiconductor material with a band gap of 0.95 eV. Pure pyrite is n-type, in both crystal and thin-film forms due to sulfur vacancies in the pyrite crystal structure acting as n-dopants. During the early years of the 20th century, pyrite was used as a mineral detector in radio receivers, is still used by crystal radio hobbyists; until the vacuum tube matured, the crystal detector was the most sensitive and dependable detector available – with considerable variation between mineral types and individual samples within a particular type of mineral. Pyrite detectors occupied a midway point between galena detectors and the more mechanically complicated perikon mineral pairs. Pyrite detectors can be as sensitive as a modern 1N34A germanium diode detector. Pyrite has been proposed as an abundant, non-toxic, inexpensive material in low-cost photovoltaic solar panels. Synthetic iron sulfide was used with copper sulfide to create the photovoltaic material.. More recent efforts are working toward thin-film solar cells made of pyrite.
Pyrite is used to make marcasite jewelry. Marcasite jewelry, made from small faceted pieces of pyrite set in silver, was known since ancient times and was popular in the Victorian era. At the time when the term became common in jewelry making, "marcasite" referred to all iron sulfides including pyrite, not to the orthorhombic FeS2 mineral marcasite, lighter in color and chemically unstable, thus not suitable for jewelry making. Marcasite jewelry does not contain the mineral marcasite. China represents the main importing country with an import of around 376,000 tonnes, which resulted at 45% of total global imports. China is the fastest growing in terms of the unroasted iron pyrites imports, with a CAGR of +27.8% from 2007 to 2016. In value terms, China constitutes the largest market for imported unroasted iron pyrites worldwide, making up 65% of global imports. From the perspective of classical inorganic chemistry, which assigns formal oxidation states to each atom, pyrite is best described as Fe2+S22−.
This formalism recognizes. These persulfide units can be viewed as derived from hydrogen disulfide, H2S2, thus pyrite would be more descriptively, not iron disulfide. In contrast, molybdenite, MoS2, features isolated sulfide centers and the oxidation state of molybdenum is Mo4+; the mineral arsenopyrite has the formula FeAsS. Whereas pyrite has S2 subunits, arsenopyrite has units, formally derived from deprotonation of H2AsSH. Analysis of classical oxidation states would recommend the description of arsenopyrite as Fe3+3−. Iron-pyrite FeS2 represents the prototype compound of the crystallographic pyrite structure; the structure is simple cubic and was among the first crystal structures solved by X-ray diffraction. It belongs to the crystallographic space group Pa3 and is denoted by the Strukturbericht notation C2. Under thermodynamic standard conditions the lattice constant a of stoichiometric iron pyrite FeS2 amounts to 541.87 pm. The unit cell is composed of a Fe face-centered cubic sublattice into.
The pyrite structure is used by other compounds MX2 of trans
Bolinas Lagoon is a tidal estuary 1,100 acres in area, located in the West Marin region of Marin County, United States, adjacent to the town of Bolinas. It is a part of the Greater Farallones National Marine Sanctuary and is considered to be among the possible landing spots of Sir Francis Drake on the west coast of North America in 1579; the lagoon is a back bay of Bolinas Bay on the Pacific coast 15 mi northwest of San Francisco. The trough in which the lagoon sits was formed by the San Andreas Fault, which runs directly through it; the lagoon is separated from the main bay by a small spit of land, known as Stinson Beach, the sand bar that encloses this lagoon is full of beachgoers and surfers on hot days, seeking to escape the heat and the urban Bay Area. State Route 1, the Shoreline Highway, runs along the eastern edge of the lagoon. Bolinas Lagoon is on the list of wetlands of international importance as defined by the Ramsar Convention for the conservation and sustainable utilization of wetlands.
Portions of the lagoon are included in Marin County’s Bolinas Lagoon Open Space Preserve, the western shore is part of the Golden Gate National Recreation Area. The lagoon has a 16.7-square-mile watershed. Kent Island is located in the lagoon. Duxbury Reef State Marine Conservation Area lies offshore from Bolinas. Like an underwater park, this protected marine area helps conserve ocean wildlife and marine ecosystems. Drakes Bay New Albion Notes Media related to Bolinas, California at Wikimedia Commons
The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
Wilkins Gulch is a valley in western Marin County, United States, located northwest of Pike County Gulch. It is associated with a small stream; the stream descends the western slope of Bolinas Ridge, crosses State Route 1, drains into Bolinas Lagoon. List of watercourses in the San Francisco Bay Area
California State Route 1
California State Route 1 is a major north–south state highway that runs along most of the Pacific coastline of the U. S. state of California. At a total of just over 659 miles, it is the longest state route in California. SR 1 has several portions designated as either Pacific Coast Highway, Cabrillo Highway, Shoreline Highway, or Coast Highway, its southern terminus is at Interstate 5 near Dana Point in Orange County and its northern terminus is at U. S. Route 101 near Leggett in Mendocino County. SR 1 at times runs concurrently with US 101, most notably through a 54-mile stretch in Ventura and Santa Barbara counties, across the Golden Gate Bridge; the highway is designated as an All-American Road. In addition to providing a scenic route to numerous attractions along the coast, the route serves as a major thoroughfare in the Greater Los Angeles Area, the San Francisco Bay Area, several other coastal urban areas. SR 1 was built piecemeal in various stages, with the first section opening in the Big Sur region in the 1930s.
However, portions of the route had several numbers over the years as more segments opened. It was not until the 1964 state highway renumbering that the entire route was designated as SR 1. Although SR 1 is a popular route for its scenic beauty, frequent landslides and erosion along the coast have caused several segments to be either closed for lengthy periods for repairs, or re-routed inland. SR 1 is part of the California Freeway and Expressway System, through the Los Angeles metro area, Santa Cruz, San Francisco metro area, Leggett is part of the National Highway System, a network of highways that are considered essential to the country's economy and mobility by the Federal Highway Administration. SR 1 is eligible to be included in the State Scenic Highway System; the Big Sur section from San Luis Obispo to Carmel is an official National Scenic Byway. The entire route is designated as a Blue Star Memorial Highway to recognize those in the United States armed forces. In Southern California, the California State Legislature has designated the segment between Interstate 5 in Dana Point and US 101 near Oxnard as the Pacific Coast Highway.
Between US 101 at the Las Cruces junction and US 101 in Pismo Beach, between US 101 in San Luis Obispo and Interstate 280 in San Francisco, the legislature has designated SR 1 as the Cabrillo Highway, after the explorer Juan Rodríguez Cabrillo who sailed along the coast line. The legislature has designated the route as the Shoreline Highway between the Manzanita Junction near Marin City and Leggett. Smaller segments of the highway have been assigned several other names by the state and municipal governments; the legislature has relinquished state control of segments within Dana Point, Newport Beach, Santa Monica, Oxnard. In addition to connecting the coastal cities and communities along its path, SR 1 provides access to beaches and other attractions along the coast, making it a popular route for tourists; the route annually helps bring several billion dollars to the state's tourism industry. The route runs right besides the coastline, or close to it, for the most part, it turns several miles inland to avoid several federally controlled or protected areas such as Vandenberg Air Force Base, Diablo Canyon Power Plant and Point Reyes National Seashore.
Segments of SR 1 range from a rural two-lane road to an urban freeway. Because of the former, long distance thru traffic traveling between the coastal metropolitan areas are instead advised to use faster routes such as US 101 or I-5. At its southernmost end in Orange County, SR 1 terminates at I-5 in Capistrano Beach in Dana Point, it travels west into the city center. After leaving Dana Point, Pacific Coast Highway becomes "Coast Highway" while at the same time continues northwest along the coast through Laguna Beach and Crystal Cove State Park. SR 1 enters Newport Beach and passes through several affluent neighborhoods, including Newport Coast and Corona Del Mar, spans the entrance to the Upper Newport Bay, which marks the boundary between East Coast Highway and West Coast Highway, crosses California State Route 55 near its southern terminus. Upon entering Huntington Beach, SR 1 regains the Pacific Coast Highway designation, it passes Huntington State Beach and the southern terminus of California State Route 39 before reaching Bolsa Chica State Beach and the Bolsa Chica Ecological Reserve.
PCH continues along the coast into Seal Beach, the final city on its journey in Orange County. PCH enters the city of Long Beach after crossing the San Gabriel River. SR 1 continues northwest through the city to its junction with Lakewood Boulevard and Los Coyotes Diagonal at the Los Alamitos Circle, more than 2 miles from the coast. From the traffic circle, it continues inland west through Long Beach, including one mile adjacent to the southern boundary of Signal Hill. PCH is marked as such in Long Beach, but bore the name of Hathaway Avenue east of the traffic circle and State Street west of there. PCH passes through the Los Angeles districts of Wilmington and Harbor City. While bypassing the immediate coastline of Palos Verdes, SR 1 continues to head west
Geographic coordinate system
A geographic coordinate system is a coordinate system that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are chosen such that one of the numbers represents a vertical position and two or three of the numbers represent a horizontal position. A common choice of coordinates is latitude and elevation. To specify a location on a plane requires a map projection; the invention of a geographic coordinate system is credited to Eratosthenes of Cyrene, who composed his now-lost Geography at the Library of Alexandria in the 3rd century BC. A century Hipparchus of Nicaea improved on this system by determining latitude from stellar measurements rather than solar altitude and determining longitude by timings of lunar eclipses, rather than dead reckoning. In the 1st or 2nd century, Marinus of Tyre compiled an extensive gazetteer and mathematically-plotted world map using coordinates measured east from a prime meridian at the westernmost known land, designated the Fortunate Isles, off the coast of western Africa around the Canary or Cape Verde Islands, measured north or south of the island of Rhodes off Asia Minor.
Ptolemy credited him with the full adoption of longitude and latitude, rather than measuring latitude in terms of the length of the midsummer day. Ptolemy's 2nd-century Geography used the same prime meridian but measured latitude from the Equator instead. After their work was translated into Arabic in the 9th century, Al-Khwārizmī's Book of the Description of the Earth corrected Marinus' and Ptolemy's errors regarding the length of the Mediterranean Sea, causing medieval Arabic cartography to use a prime meridian around 10° east of Ptolemy's line. Mathematical cartography resumed in Europe following Maximus Planudes' recovery of Ptolemy's text a little before 1300. In 1884, the United States hosted the International Meridian Conference, attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich, England as the zero-reference line; the Dominican Republic voted against the motion, while Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911.
In order to be unambiguous about the direction of "vertical" and the "horizontal" surface above which they are measuring, map-makers choose a reference ellipsoid with a given origin and orientation that best fits their need for the area they are mapping. They choose the most appropriate mapping of the spherical coordinate system onto that ellipsoid, called a terrestrial reference system or geodetic datum. Datums may be global, meaning that they represent the whole Earth, or they may be local, meaning that they represent an ellipsoid best-fit to only a portion of the Earth. Points on the Earth's surface move relative to each other due to continental plate motion and diurnal Earth tidal movement caused by the Moon and the Sun; this daily movement can be as much as a metre. Continental movement can be up to 10 m in a century. A weather system high-pressure area can cause a sinking of 5 mm. Scandinavia is rising by 1 cm a year as a result of the melting of the ice sheets of the last ice age, but neighbouring Scotland is rising by only 0.2 cm.
These changes are insignificant if a local datum is used, but are statistically significant if a global datum is used. Examples of global datums include World Geodetic System, the default datum used for the Global Positioning System, the International Terrestrial Reference Frame, used for estimating continental drift and crustal deformation; the distance to Earth's center can be used both for deep positions and for positions in space. Local datums chosen by a national cartographical organisation include the North American Datum, the European ED50, the British OSGB36. Given a location, the datum provides the latitude ϕ and longitude λ. In the United Kingdom there are three common latitude and height systems in use. WGS 84 differs at Greenwich from the one used on published maps OSGB36 by 112 m; the military system ED50, used by NATO, differs from about 120 m to 180 m. The latitude and longitude on a map made against a local datum may not be the same as one obtained from a GPS receiver. Coordinates from the mapping system can sometimes be changed into another datum using a simple translation.
For example, to convert from ETRF89 to the Irish Grid add 49 metres to the east, subtract 23.4 metres from the north. More one datum is changed into any other datum using a process called Helmert transformations; this involves converting the spherical coordinates into Cartesian coordinates and applying a seven parameter transformation, converting back. In popular GIS software, data projected in latitude/longitude is represented as a Geographic Coordinate System. For example, data in latitude/longitude if the datum is the North American Datum of 1983 is denoted by'GCS North American 1983'; the "latitude" of a point on Earth's surface is the angle between the equatorial plane and the straight line that passes through that point and through the center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels, as they are parallel to the Equator and to each other; the North Pole is 90° N. The 0° parallel of latitude is designated the Equator, the fun
Audubon Canyon is a coastal valley in Marin County, United States, associated with a small stream. The canyon provides habitat for a variety of plants. Notably, its redwoods provide nesting sites for great blue herons, great egrets, snowy egrets; the stream descends the western slope of Bolinas Ridge, crosses State Route 1, drains into Bolinas Lagoon about 3 miles north of Stinson Beach, California. Audubon Canyon Ranch, a private land preservation organization based in the North Bay, has preserved much of the canyon as part of its Martin Griffin Preserve, named after L. Martin Griffin, Jr. an environmentalist who helped save the area in the 1960s and founded the organization. The canyon was designated a National Natural Landmark in 1968. Several local chapters of the National Audubon Society, Marin Audubon Society and Golden Gate Audubon Society of the East Bay and San Francisco, organized to purchase property for the protection of heron and egret nesting sites. Golden Gate Biosphere Reserve List of watercourses in the San Francisco Bay Area Pike County Gulch Stinson Gulch Official website