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57-579: In 2023, Calarcá had an estimated population of 75,979. Located along the Colombian coffee growing axis , it was made part of the "Coffee Cultural Landscape" UNESCO World Heritage Site in 2011. The name derived from an indigenous chief of the Pijaos Tribe, who lived in this land. According to the legends, this chief died in a fight with an indigenous converted into the Catholicism, Baltazar Maldonado, to keep

114-687: A = 10 Å and c = 8.5 Å , while the structural unit cell is hexagonal (i.e. a rhombic prism ), having approximate dimensions a = 5 Å and c = 17 Å . For the same orientation, c must be multiplied by 4 to convert from morphological to structural units. As an example, calcite cleavage is given as "perfect on {1 0 1 1}" in morphological coordinates and "perfect on {1 0 1 4}" in structural units. In { h k l } {\displaystyle \{hkl\}} indices, these are {1 0 1} and {1 0 4}, respectively. Twinning , cleavage and crystal forms are often given in morphological units. The diagnostic properties of calcite include

171-548: A Paisa farmer wearing a carriel , aguadeño hat and poncho , and accompanied by a mule, has become a triumph of advertising communication. Juan Valdez has been considered in United States as the advertising image of greater recall among the inhabitants of that country in the year 2005. Eighteen urban settlements across six sites within the coffee axis and extending southwards into the Valle del Cauca department were inscribed on

228-436: A dissolution and reprecipitation mechanism, with the reaction rate controlled by the surface area of a calcite crystal. The second stage of the reaction is approximately 10 times slower. However, crystallization of calcite has been observed to be dependent on the starting pH and concentration of magnesium in solution. A neutral starting pH during mixing promotes the direct transformation of ACC into calcite without

285-548: A butterfly-shaped structure of 640 m. Since the collections of medicinal plants, heliconias, and cactus, are accompanied by gardens that delight the senses. Peñas Blancas (English: white cliffs ) consists of a crag and three vertical rock faces located on the western slopes of the Central Cordillera of the Andes near Calarcá. The bright white color of the rock walls is due to the presence of calcite and limestone . There are

342-607: A clear piece of calcite to appear doubled. The birefringent effect (using calcite) was first described by the Danish scientist Rasmus Bartholin in 1669. At a wavelength of about 590 nm, calcite has ordinary and extraordinary refractive indices of 1.658 and 1.486, respectively. Between 190 and 1700 nm, the ordinary refractive index varies roughly between 1.9 and 1.5, while the extraordinary refractive index varies between 1.6 and 1.4. Calcite has thermoluminescent properties mainly due to manganese divalent ( Mn ). An experiment

399-423: A defining Mohs hardness of 3, a specific gravity of 2.71 and, in crystalline varieties, a vitreous luster . Color is white or none, though shades of gray, red, orange, yellow, green, blue, violet, brown, or even black can occur when the mineral is charged with impurities. Calcite has numerous habits, representing combinations of over 1000 crystallographic forms . Most common are scalenohedra , with faces in

456-538: A large number of solutional caves and rock shelters inside the cliff, but access is very difficult. The caves are believed by some local people to be the location of a legendary treasure hidden by an indigenous Pijao tribal leader, the Cacique Calarcá (from whom the nearby town derives its name), during his battle against the Spanish colonialists The cliffs are a landmark of the region, and can be seen clearly from

513-405: A monohydrocalcite intermediate, sequestering carbon . Calcite is often the primary constituent of the shells of marine organisms , such as plankton (such as coccoliths and planktic foraminifera ), the hard parts of red algae , some sponges , brachiopods , echinoderms , some serpulids , most bryozoa , and parts of the shells of some bivalves (such as oysters and rudists ). Calcite

570-526: A vaterite intermediate. But when ACC forms in a solution with a basic initial pH, the transformation to calcite occurs via metastable vaterite, following the pathway outlined above. Magnesium has a noteworthy effect on both the stability of ACC and its transformation to crystalline CaCO 3 , resulting in the formation of calcite directly from ACC, as this ion destabilizes the structure of vaterite. Epitaxial overgrowths of calcite precipitated on weathered cleavage surfaces have morphologies that vary with

627-558: Is a part of the Paisa region in the rural area of Colombia . It is famous for growing and producing the majority of Colombian coffee . There are four departments in the area: Caldas , Quindío , Risaralda and Tolima . The most visited cities are Manizales , Armenia , Pereira , and Ibagué . Coffee was first grown commercially in Colombia in Salazar de las Palmas , north of Santander, and over

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684-441: Is designed to promote sustainable development in the mining industry. Calcite can help synthesize precipitated calcium carbonate (PCC) (mainly used in the paper industry) and increase carbonation . Furthermore, due to its particular crystal habit, such as rhombohedron, hexagonal prism, etc., it promotes the production of PCC with specific shapes and particle sizes. Calcite, obtained from an 80 kg sample of Carrara marble ,

741-437: Is divided into low-magnesium and high-magnesium calcite, with the dividing line placed at a composition of 4% magnesium. High-magnesium calcite retains the calcite mineral structure, which is distinct from that of dolomite , MgCa(CO 3 ) 2 . Calcite can also contain small quantities of iron and manganese . Manganese may be responsible for the fluorescence of impure calcite, as may traces of organic compounds. Calcite

798-741: Is found all over the world, and its leading global distribution is as follows: Calcite is found in many different areas in the United States. One of the best examples is the Calcite Quarry in Michigan. The Calcite Quarry is the largest carbonate mine in the world and has been in use for more than 85 years. Large quantities of calcite can be mined from these sizeable open pit mines. Calcite can also be found throughout Canada, such as in Thorold Quarry and Madawaska Mine, Ontario, Canada. Abundant calcite

855-459: Is found in spectacular form in the Snowy River Cave of New Mexico as mentioned above, where microorganisms are credited with natural formations. Trilobites , which became extinct a quarter billion years ago , had unique compound eyes that used clear calcite crystals to form the lenses. It also forms a substantial part of birds' eggshells, and the δ C of the diet is reflected in the δ C of

912-524: Is known as lublinite . Cleavage is usually in three directions parallel to the rhombohedron form. Its fracture is conchoidal , but difficult to obtain. Scalenohedral faces are chiral and come in pairs with mirror-image symmetry; their growth can be influenced by interaction with chiral biomolecules such as L- and D- amino acids . Rhombohedral faces are not chiral. Calcite is transparent to opaque and may occasionally show phosphorescence or fluorescence . A transparent variety called " Iceland spar "

969-680: Is located 4° 33’ 0.6” north and 75° 39’ 00” west. It lies in the Andean zone flanking the Central Cordillera, east of the department of Quindío in the centre-western part of the country, within the area known as the Eje Cafetero ("Coffee Axis"). Calarcá is bordered by the municipalities of Salento to the north, Cajamarca in Tolima to the east, Córdoba , Buenavista , Pijao in Quindío and Caicedonia in

1026-757: Is mined in the Santa Eulalia mining district, Chihuahua, Mexico. Large quantities of calcite in Iceland are concentrated in the Helgustadir mine . The mine was once the primary mining location of "Iceland spar." However, it currently serves as a nature reserve, and calcite mining will not be allowed. Calcite is found in parts of England, such as Alston Moor, Egremont, and Frizington, Cumbria. St. Andreasberg, Harz Mountains, and Freiberg, Saxony can find calcite. Ancient Egyptians carved many items out of calcite, relating it to their goddess Bast , whose name contributed to

1083-554: Is one of the minerals that has been shown to catalyze an important biological reaction, the formose reaction , and may have had a role in the origin of life. Interaction of its chiral surfaces (see Form ) with aspartic acid molecules results in a slight bias in chirality; this is one possible mechanism for the origin of homochirality in living cells. Climate change is exacerbating ocean acidification , possibly leading to lower natural calcite production. The oceans absorb large amounts of CO 2 from fossil fuel emissions into

1140-594: Is the National Park of Culture Agriculture - 'Panaca' , also located in the Municipality of Quimbaya in Quindio. Its key feature is that, unlike zoos, visitors are immersed in a personal and direct contact with farm animals and also enjoy scheduled activities and events with those animals. Other attractions in the area include: Tourist excursions offer trekking to some of Colombia's top coffee cultivating land as well as

1197-592: Is the Casa de los Téllez, the building of the Hospital la Misericordia, and the structure of the Rafael Uribe Uribe school. In 1999, the city was partially destroyed as a result of an earthquake , which affected the department. This made the city lose part of the architectural heritage. The municipality of Calarcá is located between 4° 20’ 40” and 4° 33’ 50” north and between 75° 33’ 40” and 75° 48’ 40” west. The inner city

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1254-403: Is the leading cause of excessive growth of cyanobacteria. As an active capping material, calcite can help reduce P release from sediments into the water, thus inhibiting cyanobacteria overgrowth. Calcite is a common constituent of sedimentary rocks , limestone in particular, much of which is formed from the shells of dead marine organisms. Approximately 10% of sedimentary rock is limestone. It

1311-474: Is the primary mineral in metamorphic marble . It also occurs in deposits from hot springs as a vein mineral; in caverns as stalactites and stalagmites ; and in volcanic or mantle-derived rocks such as carbonatites , kimberlites , or rarely in peridotites . Cacti contain Ca-oxalate biominerals. Their death releases these biominerals into the environment, which subsequently transform to calcite via

1368-586: Is used as the IAEA -603 isotopic standard in mass spectrometry for the calibration of δ O and δ C . Calcite can be formed naturally or synthesized. However, artificial calcite is the preferred material to be used as a scaffold in bone tissue engineering due to its controllable and repeatable properties. Calcite can be used to alleviate water pollution caused by the excessive growth of cyanobacteria . Lakes and rivers can lead to cyanobacteria blooms due to eutrophication , which pollutes water resources. Phosphorus (P)

1425-524: Is used for optical purposes. Acute scalenohedral crystals are sometimes referred to as "dogtooth spar" while the rhombohedral form is sometimes referred to as "nailhead spar". The rhombohedral form may also have been the " sunstone " whose use by Viking navigators is mentioned in the Icelandic Sagas . Single calcite crystals display an optical property called birefringence (double refraction). This strong birefringence causes objects viewed through

1482-448: The a 1 , a 2 , c {\displaystyle a_{1},a_{2},c} directions, or four Bravais–Miller indices h, k, i, l in the a 1 , a 2 , a 3 , c {\displaystyle a_{1},a_{2},a_{3},c} directions, where i {\displaystyle i} is redundant but useful in visualizing permutation symmetries . To add to

1539-612: The UNESCO World Heritage List in 2011 as the Coffee Cultural Landscape. These sites are representative of the entire coffee axis, preserving multiple different forms of traditional coffee growing, in addition to the culture of the region and the locations of several unique festivals. The World Heritage site is composed of many of the urban centers within the region, including Armenia , Calarcá , Salamina , Pereira , and Riosucio , as well as smaller towns and

1596-514: The Valle del Cauca to the south, and La Tebaida y Armenia to the west. The municipality has an area of 219.23 km. Urban area is 2.44 km. Rural area is 216.79 km. It varies in altitude between 1000 m above sea level at the confluence of the Quindío y Barragán rivers to 3667 m above sea level in the El Campanario highland area. Calarcá has subtropical highland climate with an average of 20 °C. Just like in others towns in

1653-408: The 1930s) the coffee arrived in the region and Calarcá became in one of the most important producers of the region and whole the country. The wealthy generated by the coffee, allowed the city to reach good conditions of developed and a cultural progress, which started to characterize the city as a cradle of poets, such as Luis Vidales and Bauidilio Montoya. The city is host to different events, such as

1710-534: The Quindío, the economy is based on Colombian coffee crops, plantain and manioc . Another important source of income is money remittance from people working in other countries to their families. Ecotourism is also strongly supported in the area. Just outside the town is the Quindío Botanical Garden , which opened in 1985, and includes an outdoor butterfly house that contains more than 1,200 species of butterflies native to Colombia, housed inside

1767-690: The calcite of the shell. The largest documented single crystal of calcite originated from Iceland, measured 7 m × 7 m × 2 m (23 ft × 23 ft × 6.6 ft) and 6 m × 6 m × 3 m (20 ft × 20 ft × 9.8 ft) and weighed about 250 tons. Classic samples have been produced at Madawaska Mine , near Bancroft, Ontario . Bedding parallel veins of fibrous calcite, often referred to in quarrying parlance as beef , occur in dark organic rich mudstones and shales, these veins are formed by increasing fluid pressure during diagenesis . Calcite formation can proceed by several pathways, from

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1824-472: The classical terrace ledge kink model to the crystallization of poorly ordered precursor phases like amorphous calcium carbonate (ACC) via an Ostwald ripening process, or via the agglomeration of nanocrystals. The crystallization of ACC can occur in two stages. First, the ACC nanoparticles rapidly dehydrate and crystallize to form individual particles of vaterite . Second, the vaterite transforms to calcite via

1881-411: The complications, there are also two definitions of unit cell for calcite. One, an older "morphological" unit cell, was inferred by measuring angles between faces of crystals, typically with a goniometer , and looking for the smallest numbers that fit. Later, a "structural" unit cell was determined using X-ray crystallography . The morphological unit cell is rhombohedral , having approximate dimensions

1938-641: The country's native palm tree - the Wax Palm , which grows up to 60 metres tall. Calcite Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO 3 ). It is a very common mineral, particularly as a component of limestone . Calcite defines hardness 3 on the Mohs scale of mineral hardness , based on scratch hardness comparison . Large calcite crystals are used in optical equipment, and limestone composed mostly of calcite has numerous uses. Other polymorphs of calcium carbonate are

1995-518: The departments of Caldas, Risaralda, Quindío and Tolima is known as the Coffee Zone because of the large development experienced by the cultivation of this product. This region was strongly affected by an earthquake that was 6.4 on the Richter scale on January 25, 1999, but subsequently the region's economy recovered rapidly. Weather conditions (8 °C to 24 °C), geographical (Andean Rainforest) and

2052-437: The expansion and eventual collapse of cave systems, resulting in various forms of karst topography . Calcite exhibits an unusual characteristic called retrograde solubility: it is less soluble in water as the temperature increases. Calcite is also more soluble at higher pressures. Pure calcite has the composition CaCO 3 . However, the calcite in limestone often contains a few percent of magnesium . Calcite in limestone

2109-484: The following reaction The carbon dioxide released by this reaction produces a characteristic effervescence when a calcite sample is treated with an acid. Due to its acidity, carbon dioxide has a slight solubilizing effect on calcite. The overall reaction is If the amount of dissolved carbon dioxide drops, the reaction reverses to precipitate calcite. As a result, calcite can be either dissolved by groundwater or precipitated by groundwater, depending on such factors as

2166-412: The geological region, determine the production of high quality coffee, with relatively short harvest periods. Farmers in the area have developed techniques for growing, harvesting and processing of grain, and all done "grain by grain", and have retained this form of processing industry despite new techniques of mass agricultural industrialization. The famous advertising icon " Juan Valdez ", represented by

2223-732: The glow curve peaks, it was found that Pb and Mn acted as activators in the calcite lattice, but Pb was much less efficient than Mn . Measuring mineral thermoluminescence experiments usually use x-rays or gamma-rays to activate the sample and record the changes in glowing curves at a temperature of 700–7500 K. Mineral thermoluminescence can form various glow curves of crystals under different conditions, such as temperature changes, because impurity ions or other crystal defects present in minerals supply luminescence centers and trapping levels. Observing these curve changes also can help infer geological correlation and age determination. Calcite, like most carbonates, dissolves in acids by

2280-464: The hexagonal {2 1 1} directions (morphological unit cell) or {2 1 4} directions (structural unit cell); and rhombohedral, with faces in the {1 0 1} or {1 0 4} directions (the most common cleavage plane). Habits include acute to obtuse rhombohedra, tabular habits, prisms , or various scalenohedra . Calcite exhibits several twinning types that add to the observed habits. It may occur as fibrous, granular, lamellar, or compact. A fibrous, efflorescent habit

2337-496: The history of the municipalities of Quindío until the foundation of the department in 1966. The local history is placed in the context of wider events in Colombia. 4°32′N 75°39′W  /  4.533°N 75.650°W  / 4.533; -75.650 Colombian coffee growing axis The Colombian coffee region ( Spanish : Eje Cafetero ), also known as the Coffee Triangle ( Spanish : Triángulo del Café )

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2394-510: The minerals aragonite and vaterite . Aragonite will change to calcite over timescales of days or less at temperatures exceeding 300 °C, and vaterite is even less stable. Calcite is derived from the German Calcit , a term from the 19th century that came from the Latin word for lime , calx (genitive calcis ) with the suffix -ite used to name minerals. It is thus a doublet of

2451-498: The national festival of the coffee, the Desfile del Yipao where different Jeep Willys (a characteristic car of the region) are customized by their owner and parade through the city, and the national meeting of writers. Historic and colonial architecture is still preserved, with houses of baroque and tapia tread, which are accompanied by innumerable stories, tradition, large balconies, colorful gates, and mud roofs. Among many others, there

2508-631: The nearby towns of Armenia and Calarcá. They offer opportunities for rock climbing and abseiling (rappeling) up to heights of 80 meters, as well as a 40-meter zip-line (zip-slide), ecological trails of 3.2 km and 9 km, and camping and a restaurant. From the foot of the cliffs there are fine views of Armenia, Calarca and the surrounding area. Lopera Gutiérrez, Jaime, La Colonización del Quindío . Loaiza Piedrahita, Oscar (2004), Los corredores del tiempo: Guía turística por la historia del Quindío . ISBN   958-33-7088-6 . Book in Spanish on

2565-427: The ocean at the time they became mineralised, and retained this mineralogy for the remainder of their evolutionary history. Petrographic evidence for these calcite sea conditions consists of calcitic ooids , lmc cements, hardgrounds , and rapid early seafloor aragonite dissolution. The evolution of marine organisms with calcium carbonate shells may have been affected by the calcite and aragonite sea cycle. Calcite

2622-417: The power of the territory, in a fight placed on Peñas Blancas, a characteristic mountain of the city. Calarcá was founded on June 29 of 1886. The city was founded by Roman Mario Valencia and Segundo Henao, people who went from Salento making explorations through the region, in the final part of the antioqueña foundations. In the beginning the city based its economy on mining and commerce. Years later (about

2679-514: The primary inorganic precipitate of calcium carbonate in marine waters was low-magnesium calcite (lmc), as opposed to the aragonite and high-magnesium calcite (hmc) precipitated today. Calcite seas alternated with aragonite seas over the Phanerozoic , being most prominent in the Ordovician and Jurassic periods. Lineages evolved to use whichever morph of calcium carbonate was favourable in

2736-433: The sky through the crystal and then rotating it so that the two images are of equal brightness, the rings of polarized light that surround the sun can be seen even under overcast skies. Identifying the sun's location would give seafarers a reference point for navigating on their lengthy sea voyages. In World War II, high-grade optical calcite was used for gun sights, specifically in bomb sights and anti-aircraft weaponry. It

2793-549: The subsurface in response to microorganism activity, such as sulfate -dependent anaerobic oxidation of methane , where methane is oxidized and sulfate is reduced , leading to precipitation of calcite and pyrite from the produced bicarbonate and sulfide . These processes can be traced by the specific carbon isotope composition of the calcites, which are extremely depleted in the C isotope, by as much as −125 per mil PDB (δ C). Calcite seas existed in Earth's history when

2850-746: The surrounding rural coffee farmlands. The region has developed major theme parks such as the Colombian National Coffee Park located in the town of Montenegro in Quindio. In the area is also the Museum of Culture Coffee , showing the process from grain production to savoring a traditional Colombian coffee. This museum, like all the other theme parks, are replicas of the colonial city, where tourists enjoy dance performances and traditional music, panoramic views from cable car with its lush landscape, and various rides. Another unique theme park in Colombia

2907-417: The term alabaster because of the close association. Many other cultures have used the material for similar carved objects and applications. A transparent variety of calcite known as Iceland spar may have been used by Vikings for navigating on cloudy days. A very pure crystal of calcite can split a beam of sunlight into dual images, as the polarized light deviates slightly from the main beam. By observing

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2964-585: The twentieth century grew to be Colombia's primary export . When coffee was first brought into the country, the leaders tried to push the farming of coffee beans, but was met with resistance from the people because it takes about 5 years until the first harvest of the bean. In 1999 coffee revenues represented 3.7% of gross domestic product (gdp) and 37% of agricultural employment. The main coffee-producing departments are: Nariño , Norte de Santander , Antioquia , Valle del Cauca , Huila , Tolima , Caldas , Risaralda , Quindio and Cundinamarca . The area between

3021-457: The type of weathering the substrate experienced: growth on physically weathered surfaces has a shingled morphology due to Volmer-Weber growth, growth on chemically weathered surfaces has characteristics of Stranski-Krastanov growth, and growth on pristine cleavage surfaces has characteristics of Frank - van der Merwe growth. These differences are apparently due to the influence of surface roughness on layer coalescence dynamics. Calcite may form in

3078-495: The water temperature, pH , and dissolved ion concentrations. When conditions are right for precipitation, calcite forms mineral coatings that cement rock grains together and can fill fractures. When conditions are right for dissolution, the removal of calcite can dramatically increase the porosity and permeability of the rock, and if it continues for a long period of time, may result in the formation of caves . Continued dissolution of calcium carbonate-rich formations can lead to

3135-494: The word chalk . When applied by archaeologists and stone trade professionals, the term alabaster is used not just as in geology and mineralogy, where it is reserved for a variety of gypsum ; but also for a similar-looking, translucent variety of fine-grained banded deposit of calcite. In publications, two different sets of Miller indices are used to describe directions in hexagonal and rhombohedral crystals, including calcite crystals: three Miller indices h, k, l in

3192-426: Was conducted by adding activators such as ions of Mn, Fe, Co, Ni, Cu, Zn, Ag, Pb, and Bi to the calcite samples to observe whether they emitted heat or light. The results showed that adding ions ( Cu , Cu , Zn , Ag , Bi , Fe , Fe , Co , Ni ) did not react. However, a reaction occurred when both manganese and lead ions were present in calcite. By changing the temperature and observing

3249-455: Was used as a polarizer (in Nicol prisms ) before the invention of Polaroid plates and still finds use in optical instruments. Also, experiments have been conducted to use calcite for a cloak of invisibility . Microbiologically precipitated calcite has a wide range of applications, such as soil remediation, soil stabilization and concrete repair. It also can be used for tailings management and

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