Specifically, in America, deposits have been found in Arizona, Colorado, New Mexico, Texas, Utah, Washington, Oregon, and Idaho. ![]() Just to name a few: Argentina, Australia, Canada, Chile, Georgia, Greece, Italy, Japan, Mexico, New Zealand, Papa New Guinea, Peru, Turkey, and the United States of America. This naturally occurring volcanic glass can be found in places where there are, or were volcanoes. ![]() The human race may have evolved very differently otherwise. Think about it! We have some very brave and hairy people to thank for heading straight into a cooling lava field. Obsidian can be used as a flint starter, and coincidentally, humans started utilizing fire around the same time that obsidian was utilized. The way that obsidian fractures are so sharp, that it wouldn’t even require the tool to be sharpened into anything. Obsidian blades were often found with the remains of Homo erectus, and it is believed that these technologies developed nearly 1.76 million years ago. This age is classified through the first practices of stone tool usage. The first-ever known historical use takes us into the Acheulean age. But at the same time, it is classified as a mineraloid, since it has mineral qualities, but they are too variable to be pure mineral. It cannot be considered a mineral, because as a glass it is not crystalline, whereas minerals are. It is extremely hard, but unfortunately brittle. It’s an amorphous element, meaning that when it fractures it does so into impossibly sharp shards. High silica content in lava results in high viscosity, so when it runs it cools very quickly and turns into glass. Lapis Obsidianus is an igneous rock - ignis comes from the Latin word for “fire” - and it’s formed through the cooling and solidification of magma or lava. In order to understand the pros and cons of an obsidian blade, we must first know where it comes from. Iron and magnesium typically give the obsidian a dark green to brown to black color.Where can I find an obsidian knife? Obsidian is Literally Lava While pure obsidian is always dark in appearance, the color varies depending on the presence of impurities. Tektites were once thought by many to be obsidian produced by lunar volcanic eruptions, though few scientists now agree with this theory. The breakdown of obsidian is accelerated by the presence of water. It is sometimes classified as a Mineraloid because obsidian is metastable at the earth's surface (over time the glass becomes fine-grained mineral crystals). Its composition is very similar to that of granite and rhyolite. Obsidian is mineral-like, but not a true mineral because it is not crystalline. While a rock like basalt is dark because of ferromagnesian enrichment, obsidian consists mainly of silicon dioxide, usually 70% or more. ![]() Because of the lack of crystal structure, obsidian blade edges can reach almost molecular thinness, leading to its ancient use as arrowheads and its modern use as surgical scalpel blades. It is commonly found within the margins of felsic lava flows, where cooling is more rapid. ![]() Obsidian is a rock which is a type of naturally occurring glass, produced by volcanoes (igneous origin) when a felsic lava cools rapidly and freezes without sufficient time for crystal growth.
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