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Copal With Insects Close-up
Copal is a tree resin, particularly the aromatic resins from the copal tree '' Protium copal'' (Burseraceae) used by the cultures of pre-Columbian Mesoamerica as ceremonially burned incense and for other purposes. More generally, copal includes resinous substances in an intermediate stage of polymerization and hardening between "gummier" resins and amber. Copal that is partly mineralized is known as copaline. It is available in different forms; the hard, amber-like yellow copal is a less expensive version, while the milky-white copal is more expensive. Etymology The word "copal" is derived from the Nahuatl language word , meaning "incense". History and uses Subfossil copal is well known from New Zealand (kauri gum from ''Agathis australis'' (Araucariaceae)), Japan, the Dominican Republic, Colombia, and Madagascar. It often has inclusions and is sometimes sold as "young amber". When it is treated or enhanced in an autoclave (as is sometimes done to industrialized Baltic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copal Madagascar
Copal is a tree resin, particularly the aromatic resins from the copal tree ''Protium copal'' (Burseraceae) used by the cultures of pre-Columbian Mesoamerica as ceremonially burned incense and for other purposes. More generally, copal includes resinous substances in an intermediate stage of polymerization and hardening between "gummier" resins and amber. Copal that is partly mineralized is known as copaline. It is available in different forms; the hard, amber-like yellow copal is a less expensive version, while the milky-white copal is more expensive. Etymology The word "copal" is derived from the Nahuatl language word , meaning "incense". History and uses Subfossil copal is well known from New Zealand (kauri gum from ''Agathis australis'' (Araucariaceae)), Japan, the Dominican Republic, Colombia, and Madagascar. It often has inclusions and is sometimes sold as "young amber". When it is treated or enhanced in an autoclave (as is sometimes done to industrialized Baltic amb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetone
Acetone (2-propanone or dimethyl ketone) is an organic compound with the chemical formula, formula . It is the simplest and smallest ketone (). It is a colorless, highly Volatile organic compound, volatile, and flammable liquid with a characteristic pungent odor. Acetone is miscibility, miscible with properties of water, water and serves as an important organic solvent in industry, home, and laboratory. About 6.7 million tonnes were produced worldwide in 2010, mainly for use as a solvent and for production of methyl methacrylate and bisphenol A, which are precursors to widely used plastics.Acetone World Petrochemicals report, January 2010Stylianos Sifniades, Alan B. Levy, "Acetone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. It is a common building block in organic chemistry. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Arts Materials
The visual system is the physiological basis of visual perception (the ability to detect and process light). The system detects, transduces and interprets information concerning light within the visible range to construct an image and build a mental model of the surrounding environment. The visual system is associated with the eye and functionally divided into the optical system (including cornea and lens) and the neural system (including the retina and visual cortex). The visual system performs a number of complex tasks based on the ''image forming'' functionality of the eye, including the formation of monocular images, the neural mechanisms underlying stereopsis and assessment of distances to (depth perception) and between objects, motion perception, pattern recognition, accurate motor coordination under visual guidance, and colour vision. Together, these facilitate higher order tasks, such as object identification. The neuropsychological side of visual information ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweat Lodge
A sweat lodge is a low profile hut, typically dome-shaped or oblong, and made with natural materials. The structure is the ''lodge'', and the ceremony performed within the structure may be called by some cultures a purification ceremony or simply a sweat. Traditionally the structure is simple, constructed of saplings covered with blankets and sometimes animal skins. The induction of sweating is a spiritual ceremony – it is for prayer and healing, and it is only to be led by Indigenous Elders who know the language, songs, traditions, and safety protocols of their culture's inherited tradition. Otherwise, the ceremony can be dangerous if performed improperly. The ceremony is traditional to some Indigenous peoples of the Americas, predominantly those from the Plains cultures, but with the rise of pan-Indianism, numerous nations that did not originally have the sweat lodge ceremony have learned the ceremony from other Nations. Sweat lodges have also been imitated by many non-na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central America
Central America is a subregion of North America. Its political boundaries are defined as bordering Mexico to the north, Colombia to the southeast, the Caribbean to the east, and the Pacific Ocean to the southwest. Central America is usually defined as consisting of seven countries: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama. Within Central America is the Mesoamerican biodiversity hotspot, which extends from southern Mexico to southeastern Panama. Due to the presence of several active geologic faults and the Central America Volcanic Arc, there is a high amount of seismic activity in the region, such as volcanic eruptions and earthquakes, which has resulted in death, injury, and property damage. Most of Central America falls under the Isthmo-Colombian cultural area. Before the Spanish expedition of Christopher Columbus' voyages to the Americas, hundreds of indigenous peoples made their homes in the area. From the year 1502 onwards, Spain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indigenous Peoples Of Mexico
Indigenous peoples of Mexico (), Native Mexicans () or Mexican Native Americans (), are those who are part of communities that trace their roots back to populations and communities that existed in what is now Mexico before the arrival of Europeans. The number of Indigenous Mexicans is defined through the second article of the Constitution of Mexico, Mexican Constitution. The Censo General de Población y Vivienda, Mexican census does not classify individuals by race, using the Culture, cultural-Ethnic group, ethnicity of Indigenous communities that preserve their Indigenous languages, traditions, beliefs, and cultures. As a result, the count of Indigenous peoples in Mexico does not include those of mixed Indigenous and European heritage who have not preserved their Indigenous cultural practices. Genetic studies have found that most Mexicans are of partial Indigenous heritage. According to the National Indigenous Institute (INI) and the National Institute of Indigenous Peoples (C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suez Canal
The Suez Canal (; , ') is an artificial sea-level waterway in Egypt, Indo-Mediterranean, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez and dividing Africa and Asia (and by extension, the Sinai Peninsula from the rest of Egypt). The canal is a key trade route between Europe and Asia. In 1858, French diplomat Ferdinand de Lesseps formed the Suez Canal Company, Compagnie de Suez for the express purpose of building the canal. Construction of the canal lasted from 1859 to 1869. The canal officially opened on 17 November 1869. It offers vessels a direct route between the Atlantic Ocean#North Atlantic, North Atlantic and northern Indian Ocean, Indian oceans via the Mediterranean Sea and the Red Sea, avoiding the South Atlantic and southern Indian oceans and reducing the journey distance from the Arabian Sea to London by approximately , to 10 days at or 8 days at . The canal extends from the northern terminus of Port Said to the southern terminus of Port ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Civil War
The American Civil War (April 12, 1861May 26, 1865; also known by Names of the American Civil War, other names) was a civil war in the United States between the Union (American Civil War), Union ("the North") and the Confederate States of America, Confederacy ("the South"), which was formed in 1861 by U.S. state, states that had Secession in the United States, seceded from the Union. The Origins of the American Civil War, central conflict leading to war was a dispute over whether Slavery in the United States, slavery should be permitted to expand into the western territories, leading to more slave states, or be prohibited from doing so, which many believed would place slavery on a course of ultimate extinction. Timeline of events leading to the American Civil War, Decades of controversy over slavery came to a head when Abraham Lincoln, who opposed slavery's expansion, won the 1860 presidential election. Seven Southern slave states responded to Lincoln's victory by seceding f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zanzibar
Zanzibar is a Tanzanian archipelago off the coast of East Africa. It is located in the Indian Ocean, and consists of many small Island, islands and two large ones: Unguja (the main island, referred to informally as Zanzibar) and Pemba Island. The capital is Zanzibar City, located on the island of Unguja. Its historic centre, Stone Town, is a World Heritage Site. Zanzibar is also a Autonomous administrative divisions, semi-autonomous region that united with Tanganyika (1961–1964), Tanganyika in 1964, and formed the present-day Tanzania, United Republic of Tanzania. The archipelago's main Industry (economics), industries are spices, raffia palm, raffia, and tourism. The main spices produced are clove, nutmeg, cinnamon, coconut, and black pepper. The Zanzibar Archipelago, together with Tanzania's Mafia Island, are sometimes referred to locally as the "Spice Islands". Tourism in Zanzibar is a more recent activity, driven by government promotion that caused an increase from 19,000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varnish
Varnish is a clear Transparency (optics), transparent hard protective coating or film. It is not to be confused with wood stain. It usually has a yellowish shade due to the manufacturing process and materials used, but it may also be pigmented as desired. It is sold commercially in various shades. Varnish is primarily used as a wood finishing, wood finish where, stained or not, the distinctive tones and grains in the wood are intended to be visible. Varnish finishes are naturally Gloss (material appearance), glossy, but satin/semi-gloss and flat sheens are available. History The word "varnish" comes from Mediaeval Latin ''vernix'', meaning odorous resin, perhaps derived from Middle Greek ''berōnikón'' or ''beroníkē'', meaning amber or amber-colored glass. A false etymology traces the word to the Greek ''Berenice'', the ancient name of modern Benghazi in Libya, where the first varnishes in the Mediterranean area were supposedly used and where resins from the trees of now-v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subfossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of ''Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Africa
East Africa, also known as Eastern Africa or the East of Africa, is a region at the eastern edge of the Africa, African continent, distinguished by its unique geographical, historical, and cultural landscape. Defined in varying scopes, the region is recognized in the United Nations Statistics Division United Nations geoscheme for Africa, scheme as encompassing 18 sovereign states and 4 territories. It includes the Horn of Africa to the North and Southeastern Africa to the south. Definitions In a narrow sense, particularly in English-speaking contexts, East Africa refers to the area comprising Kenya, Tanzania, and Uganda, largely due to their shared history under the Omani Empire and as parts of the British East Africa Protectorate and German East Africa. Further extending East Africa's definition, the Horn of Africa—comprising Djibouti, Eritrea, Ethiopia, and Somalia—stands out as a distinct geopolitical entity within East Africa.Robert Stock, ''Africa South of the Sahara, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
