Lithic analysis can be instrumental in understanding prehispanic groups in Mesoamerica. Modern archaeologists have developed a relative dating system, obsidian hydration dating, to calculate the age of obsidian artifacts. It was also polished to create early mirrors. Like all glass and some other types of naturally occurring rocks, obsidian breaks with a characteristic conchoidal fracture. Obsidian was valued in Stone Age cultures because, like flint, it could be fractured to produce sharp blades or arrowheads. 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, Greece, El Salvador, Guatemala, Iceland, Italy, Japan, Kenya, Mexico, New Zealand, Peru, Scotland and United States.
Obsidian can be found in locations which have experienced rhyolitic eruptions. These bubbles can produce interesting effects such as a golden sheen (sheen obsidian) or an iridescent, rainbow-like sheen (rainbow obsidian).
It may contain patterns of gas bubbles remaining from the lava flow, aligned along layers created as the molten rock was flowing before being cooled. In some stones, the inclusion of small, white, radially clustered crystals of cristobalite in the black glass produce a blotchy or snowflake pattern (snowflake obsidian).
Iron and magnesium typically give the obsidian a dark green to brown to black color. Pure obsidian is usually dark in appearance, though the color varies depending on the presence of impurities. 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.
MAHOGANY OBSIDIAN RAW FREE
If you are unsure about what you need, please visit our Flintknapping Buyer's Guide, or feel free to contact us and we will be glad to help. If you are graduating to this size material from one of our kits, we recommend adding a large copper percussion billet to your order. Attempting to knap large stone with too small of a billet will damage the billet and not produce sizable thinning flakes early on in the process as needed. Large knapping material requires large billets. In efforts to avoid defects as much as possible, we perform a few thinning blows to ensure that you do not pay for large amounts of waste, over thick spalls, or fragile/thin sizes that will shatter with the first strike. On some spalls however, blemishes do get past us because not all defects are evident at first or even second inspection. We strive to provide the cleanest, blemish free knapping material within our means. WARNING: Obsidian flakes can be sharper than razor blades! Exercise extreme caution!
MAHOGANY OBSIDIAN RAW FULL
To make certain you receive the full range of sizes of this material you will need to order multiple pounds or purchase a flat rate box of material. Most often a one pound order will contain two pieces of stone in the approx 4 inch range. Ordering 1 pound of this material will not ensure that you will get a single 6 inch spall. This size is good for large and medium points and blades. Our cleaned and graded Mahogany Obsidian spalls range in size from 3-6 inch pieces. Mahogany Obsidian is a popular volcanic glass favored by flintknappers for its unique wood-like colorful streaks of brown/dark red and black, consistent quality, and uniform flaking. Knappers who favor pressure flaking techniques usually enjoy Obsidian in particular for its potential to run super long flakes. Medium to large spalls of #1 graded and cleaned volcanic glass with unique wood-like colorful streaks of brown/dark red and black. Sold by the pound (1-2 pieces per lb).
0 kommentar(er)
