Similar tracing techniques have allowed obsidian to be identified in Greece also as coming from Melos, Nisyros or Yiali, islands in the Aegean Sea. Each volcano and in some cases each volcanic eruption produces a distinguishable type of obsidian, making it possible for archaeologists to trace the origins of a particular artifact. Native American people traded obsidian throughout the Americas. Called a macuahuitl, the weapon was capable of inflicting terrible injuries, combining the sharp cutting edge of an obsidian blade with the ragged cut of a serrated weapon. Mesoamericans also made a type of sword with obsidian blades mounted in a wooden body. Pre-Columbian Mesoamericans’ use of obsidian was extensive and sophisticated including carved and worked obsidian for tools and decorative objects. Another example is the archeological recovery at coastal Chumash sites in California indicating considerable trade with the distant site of Casa Diablo, California in the Sierra Nevada Mountains. This is the case in Yaxchilán, a Maya city where even warfare implications have been studied linked with obsidian use and its debris. A careful analysis of obsidian in a culture or place can be of considerable use to reconstruct commerce, production, distribution and thereby understand economic, social and political aspects of a civilization. Lithic analysis can be instrumental in understanding prehispanic groups in Mesoamerica. The first attested civilized use is from excavations at Tell Brak dated the late fifth millennia. Use of obsidian in pottery of the Neolithic in the area around Lipari was found to be significantly less at a distance representing two weeks journeying.Īnatolian sources of obsidian are known to have been the material used in the Levant and modern-day Iraqi Kurdistan from a time beginning sometime about 12,500 BC. The first archaeological evidence known of usage were made from within Kariandusi and other sites of the Acheulian age (beginning 1.5 million years previously) dated 700,000 BC, although the number of objects found at these sites were very low relative to the Neolithic. Acigöl town and the Göllü Dað volcano were the most important sources in central Anatolia, one of the more important source areas in prehistoric Near East. Ancient sources in the Aegean were Melos and Giali. There are only four major deposit areas in the central Mediterranean: Lipari, Pantelleria, Palmarola and Monte Arci. states of Virginia, as well as Pennsylvania. Obsidian can also be found in the eastern U.S. states including Arizona, Colorado, New Mexico, Texas, Utah, Washington, Oregon and Idaho. Yellowstone National Park has a mountainside containing obsidian located between Mammoth Hot Springs and the Norris Geyser Basin, and deposits can be found in many other western U.S.
Obsidian flows which may be hiked on are found within the calderas of Newberry Volcano and Medicine Lake Volcano in the Cascade Range of western North America, and at Inyo Craters east of the Sierra Nevada in California. It can be found in Argentina,Armenia, Azerbaijan, Canada, Chile, Georgia, Greece, El Salvador, Guatemala, Iceland, Italy, Japan, Kenya, Mexico, New Zealand, Peru, Scotland, Turkey and the United States. Obsidian can be found in locations which have experienced rhyolitic eruptions. Pig carved in snowflake obsidian, 10 centimeters (4 in) long. This breakdown of obsidian is accelerated by the presence of water. Because obsidian is metastable at the Earth’s surface (over time the glass becomes fine-grained mineral crystals), no obsidian has been found that is older than Cretaceous age. Crystalline rocks with obsidian’s composition include granite and rhyolite. Obsidian consists mainly of SiO2 (silicon dioxide), usually 70% or more. Though obsidian is usually dark in color similar to mafic rocks such as basalt, obsidian’s composition is extremely felsic. It is sometimes classified as a mineraloid. Obsidian is mineral-like, but not a true mineral because as a glass it is not crystalline in addition, its composition is too complex to comprise a single mineral. Tektites were once thought by many to be obsidian produced by lunar volcanic eruptions, though few scientists now adhere to this hypothesis. Having a low water content when newly formed typically less than 1% water by weight, becomes progressively hydrated when exposed to groundwater, forming perlite. Obsidian is the rock formed as a result of cooled lava, which is the parent material. A baroque cabochon of iridescent “rainbow obsidian”.
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