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Essay On Obsidian Dating

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In dating archeological artifacts archeologist have a variety of ways in finding out the age of that artifact, but four ways in-which archeologist date artifacts are: archeomagnetism, obsidian hydration, radiocarbon dating, and tree-ring dating. Each dating system has its own advantages and disadvantages, and some are more accessible, convenient and doable.
When it comes to Archaeomagnetism dating, it is the study of and the interpretation of the Earths signature magnetic field at past times recorded in archaeological materials. These paleo magnetic signatures are fixed when ferromagnetic materials such as iron, cobalt and nickel are cooled below the Curie point, freezing the magnetic moment of the material in the direction of the local magnetic field at that time. The direction and magnitude of the magnetic field of the Earth at a particular location varies with time, and can be used to constrain the age of materials. In conjunction with techniques such as radiometric dating, …show more content…
Based on the fact that obsidian is created when lava flows on a fresh surface and rapidly cools, you date it by using a piece of obsidian in the tool manufacturing, or flint-knapping, process. Obsidian contains only about 0.2 percent water. When a piece of obsidian is fractured, atmospheric water is attracted to the surface and begins to diffuse into the glass. The hydration process continues until the fresh obsidian surface contains about 3.5 percent water. The thickness of the hydration rind can be identified in petrographic thin sections and cut into the surface and observed under a microscope. When looking under the microscope distinct diffusion front can be recognized by an abrupt change in refractive index at the inner edge of the obsidian hydration rind. These fronts or rinds of the obsidian hydration has different optical properties, this is the reason behind obsidian

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