Trent Jan 13, Jan 14, Welcome, Trent! Wonderopolis Mar 31, W Nov 4, What can mine obsidian? Also my sister has blue obsidian. Wonderopolis Nov 5, Garett Oct 28, Wonderopolis Oct 29, We're not sure, Garett! If you discover the answer, we hope you'll share it with us! Peterson Oct 28, Hello there, Peterson! Thanks for joining us here in Wonderopolis!
Mckenzie Oct 28, Dear wonderoplis how does it form into it. Sincerely McKenzie. Content Oct 28, Dear wonderopilis, I never new obsidian was igneous.
I learned a lot about obsidian. Maybe you should tell me about obsidians history. Sincerely conlen. John Oct 28, Brooke Oct 28, Dear Wonderopolis how sharp is Obsidian? You should compar it.
Maya H. Obsidian is considered a cheap luxury item. Most gemstones are rare and expensive, but obsidian, not even a jewel, is prettier than some emeralds when made smooth! I would wear obsidian jewelry. Thanks for a great Wonder today! A question: Is pbsidian associated with any myths or legends? It seems it could be, with its striking black color. Tj Oct 28, Dear Wonderpolis, It's amazing that obsidian is harder than surgical steel! How does obsidian get its glassy look? I always never new that obsidian was not a full mineral.
Also that it is a glassy type. And also I have a obsidian snow flake. Sarah lemons Oct 28, Wonderopolis Oct 28, H Oct 28, I like the text this week it was cool to find out all that information.
The Blogging Hawks Oct 28, We thought this wonder was really awesome this morning. Some of the cool things we learned from you were: - that obsidian was used for mirrors. The Blogging Hawks :. Amelia L. Can't obsidian be found in some parts of Alaska and in Hawaii?
Plus I have touched obsidian before and it was awesome! Related Wonders for You to Explore Match its definition: physics and chemistry the smallest component of an element having the chemical properties of the element. Word Match Congratulations! Share results. Despite its silicate composition, which typically produces white or clear minerals, obsidian is dark because the minerals remained mixed like a soup.
Certain mineral inclusions can give obsidian different colors. For instance, iron and magnesium can give the rock a green appearance, while hematite will produce reddish-brown hues. Obtain a geologic map of obsidian localities. The mountainous regions of the western United States have a lengthy geologic history of volcanism which created a mass of obsidian deposits. Mines, claims and other known locations are found in abundance in Arizona, California, Colorado, Oregon and Utah, among others.
To locate these regions, contact the U. A list of known mining sites can be obtained from mindat. Get permission to go rock collecting. No matter where the deposits of obsidian are located, always check with the property owner before attempting to collect on the land. Rock collecting in general is prohibited in many national and state parks, as well as mines or other commercially owned areas. Incredible moment Anak Krakatau erupts, Oct Download Google Earth For Free.
Remote Sensing Downloader. Thunder Egg. Mineral Researches Top Posts. Share on Facebook. Rainbow Obsidian Obsidian is a natural volcanic glass that is formed as an igneous rock that is extrusive. How Do Gold Nuggets Form? Recommended For You Diamond discovery under pressure. Clues from soured milk reveal how gold veins form.
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Types of Obsidian: The specimens shown above are from Glass Butte rockhounding site in central Oregon. It shows the diversity of obsidian types that can be found in a small geographic area.
Clockwise from upper left are: double flow obsidian, rainbow obsidian, black obsidian, pumpkin obsidian, mahogany obsidian, gold sheen obsidian, and the piece in the center is gold sheen. Mahogany obsidian: A tumble-polished specimen of "mahogany obsidian. Black is the most common color of obsidian. However, it can also be brown, tan, or green. Rarely, obsidian can be blue, red, orange, or yellow. The colors are thought to be caused mainly by trace elements or inclusions.
Occasionally two colors of obsidian will be swirled together in a single specimen. The most common color combination is black and brown obsidian swirled together - that's called "mahogany obsidian" see photo. As a "glass," obsidian is chemically unstable. With the passage of time, some obsidian begins to crystallize. This process does not happen at a uniform rate throughout the rock. Instead it begins at various locations within the rock. At these locations, the crystallization process forms radial clusters of white or gray cristobalite crystals within the obsidian.
When cut and polished, these specimens are referred to as "snowflake obsidian" see photos. Rarely, obsidian has an iridescent or metallic "sheen" caused by light reflecting from minute inclusions of mineral crystals, rock debris, or gas. These colored specimens are known as "rainbow obsidian," "golden obsidian," or "silver obsidian," depending upon the color of the sheen or iridescence. These specimens are very desirable for the manufacture of jewelry.
Snowflake obsidian: A tumble-polished specimen of "snowflake obsidian. Most obsidians have a composition similar to rhyolite and granite. Granites and rhyolites can form from the same magma as obsidian and are often geographically associated with the obsidian. Rarely, volcanic glasses are found with a composition similar to basalt and gabbro. These glassy rocks are named "tachylyte. Pumice , scoria , and tachylyte are other volcanic glasses formed by rapid cooling.
Pumice and scoria differ from obsidian by having abundant vesicles - cavities in the rock produced when gas bubbles were trapped in a solidifying melt.
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