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Kauri Gum
Kauri gum is resin from kauri trees ('' Agathis australis''), which historically had several important industrial uses. It can also be used to make crafts such as jewellery. Kauri forests once covered much of the North Island of New Zealand, before the arrival of people caused deforestation, causing several areas to revert to sand dunes, scrubs, and swamps. Even afterwards, ancient kauri fields continued to provide a source for the gum and the remaining forests.Hayward, pp 4–5 Kauri gum forms when resin from kauri trees leaks out through fractures or cracks in the bark, hardening with the exposure to air. Lumps commonly fall to the ground and can be covered with soil and forest litter, eventually fossilising. Other lumps form as branches forked or trees are damaged, releasing the resin.Hayward, p 2 Uses The Māori had many uses for the gum, which they called ''kapia''. Fresh gum was used as a type of chewing gum (older gum was softened by soaking and mixing with juice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kauri Gum Carving
''Agathis'', commonly known as kauri or dammara, is a genus of 22 species of evergreen tree. The genus is part of the ancient conifer family Araucariaceae, a group once widespread during the Jurassic and Cretaceous periods, but now largely restricted to the Southern Hemisphere except for a number of extant Malesian ''Agathis''.de Laubenfels, David J. 1988. Coniferales. P. 337–453 in Flora Malesiana, Series I, Vol. 10. Dordrecht: Kluwer Academic. Description Mature kauri trees have characteristically large trunks, with little or no branching below the crown. In contrast, young trees are normally conical in shape, forming a more rounded or irregularly shaped crown as they achieve maturity.Whitmore, T.C. 1977. ''A first look at Agathis''. Tropical Forestry Papers No. 11. University of Oxford Commonwealth Forestry Institute. The bark is smooth and light grey to grey-brown, usually peeling into irregular flakes that become thicker on more mature trees. The branch structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amber
Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects."Amber" (2004). In Maxine N. Lurie and Marc Mappen (eds.) ''Encyclopedia of New Jersey'', Rutgers University Press, . Amber is used in jewelry and has been used as a healing agent in folk medicine. There are five classes of amber, defined on the basis of their chemical constituents. Because it originates as a soft, sticky tree resin, amber sometimes contains animal and plant material as inclusions. Amber occurring in coal seams is also called resinite, and the term ''ambrite'' is applied to that found specifically within New Zealand coal seams. Etymology The English word ''amber'' derives from Arabic (ultimately from Middle Persian ''ambar'') via Middle Latin ''ambar'' and Middle French ''ambre''. The word was adopted in Middle English in the 14th centu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kauri At Waipoua Forest
''Agathis'', commonly known as kauri or dammara, is a genus of 22 species of evergreen tree. The genus is part of the ancient conifer family Araucariaceae, a group once widespread during the Jurassic and Cretaceous periods, but now largely restricted to the Southern Hemisphere except for a number of extant Malesian ''Agathis''.de Laubenfels, David J. 1988. Coniferales. P. 337–453 in Flora Malesiana, Series I, Vol. 10. Dordrecht: Kluwer Academic. Description Mature kauri trees have characteristically large trunks, with little or no branching below the crown. In contrast, young trees are normally conical in shape, forming a more rounded or irregularly shaped crown as they achieve maturity.Whitmore, T.C. 1977. ''A first look at Agathis''. Tropical Forestry Papers No. 11. University of Oxford Commonwealth Forestry Institute. The bark is smooth and light grey to grey-brown, usually peeling into irregular flakes that become thicker on more mature trees. The branch structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon-dating
Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The method was developed in the late 1940s at the University of Chicago by Willard Libby. It is based on the fact that radiocarbon () is constantly being created in the Earth's atmosphere by the interaction of cosmic rays with atmospheric nitrogen. The resulting combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and thereafter the amount of it contains begins to decrease as the undergoes radioactive decay. Measuring the amount of in a sample from a dead plant or animal, such as a piece of wood or a fragment of bone, provides information that can be used to calcu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Hemisphere
The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's North Pole. Owing to Earth's axial tilt of 23.439281°, winter Winter is the coldest season of the year in Polar regions of Earth, polar and temperate climates. It occurs after autumn and before spring (season), spring. The tilt of Axial tilt#Earth, Earth's axis causes seasons; winter occurs when a Hemi ... in the Northern Hemisphere lasts from the December solstice (typically December 21 UTC) to the March equinox (typically March 20 UTC), while summer lasts from the June solstice through to the September equinox (typically on 23 September UTC). The dates vary each year due to the difference between the calendar year and the Year#Astronomical years, astronomical year. Within the Northern Hemisphere, oceanic currents can change the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
