People who do rock tumbling often polish Apache Tears. They are difficult to polish because the obsidian chips and bruises easily. Success occurs when they are cushioned during the tumbling with smaller pieces of rough or small ceramic media. The manufacture of obsidian tools by humans dates back to the Stone Age. At some locations, tons of obsidian flakes reveal the presence of ancient "factories.
Making arrowheads, spear points, knife blades, and scrapers from obsidian, chert , or flint might have been the world's first "manufacturing industry. Obsidian was so valued for these uses that ancient people mined, transported, and traded obsidian and obsidian objects over distances of up to a thousand miles.
Archaeologists have been able to document the geography of this trade by matching the characteristics of obsidian in outcrops with the characteristics of obsidian in cutting tools. A study done by the Idaho National Laboratory used composition studies by X-ray fluorescence to identify the source outcrops of obsidian artifacts and map their use across the western United States. Although using a rock as a cutting tool might sound like "stone age equipment," obsidian continues to play an important role in modern surgery.
Obsidian can be used to produce a cutting edge that is thinner and sharper than the best surgical steel. Today, thin blades of obsidian are placed in surgical scalpels used for some of the most precise surgery.
In controlled studies, the performance of obsidian blades was equal to or superior to the performance of surgical steel. Obsidian jewelry: Mahogany obsidian and snowflake obsidian cabochons set in sterling silver pendants.
Obsidian for opal triplets: A thin piece of obsidian is often used as a "backing" material for opal doublets and triplets. The black obsidian adds stability to the opal and provides a dark background color that contrasts with the opal's fire. Obsidian is a popular gemstone.
It is often cut into beads and cabochons or used to manufacture tumbled stones. Obsidian is sometimes faceted and polished into highly reflective beads.
Some transparent specimens are faceted to produce interesting gems. The use of obsidian in jewelry can be limited by its durability. It has a hardness of about 5. It also lacks toughness and is easily broken or chipped upon impact.
These durability concerns make obsidian an inappropriate stone for rings and bracelets. It is best suited for use in low-impact pieces such as earrings, brooches, and pendants.
Obsidian is also used in making opal doublets and opal triplets. Thin slices or chips of opal are glued to a thin slice of obsidian to make a composite stone. The black obsidian provides an inexpensive and color-contrasting background that makes opal's colorful fire much more obvious.
It also adds mass and stability to the opal that facilitates cutting it into a gem. Freshly broken pieces of obsidian have a very high luster. Ancient people noticed that they could see a reflection in obsidian and used it as a mirror.
Later, pieces of obsidian were ground flat and highly polished to improve their reflective abilities. Obsidian's hardness of 5. Artists have used obsidian to make masks, small sculptures, and figurines for thousands of years. Article by: Hobart M. Find Other Topics on Geology. Maps Volcanoes World Maps. There are numerous federal lands in the area, making collecting limited.
Always verify BLM restrictions before collecting on public lands. The area is also called Chochetopa Hill. At present, much of the area is inaccessible to the public, being recently sold to private owners. Like most of the western states, the sources of obsidian in Nevada seem endless, but verification of the sites is often difficult to obtain.
There are a number of campsites in this area, at least some of which are under the control of the BLM. As a general rule, the BLM allows rock collecting on their lands. Here is a great place for a family outing.
The area boasts a sea of obsidian for collectors of all ages to pick up and pocket to take home. No collecting is allowed in national parks but in other areas you can usually harvest for personal use. Obsidian Ridge is one of the better locations in the state, but New Mexico has a lot of obsidian if you know where to look.
Complete Guide. Black, brown, red, and snowflake obsidian can be found here. The majority of it is on BLM lands as well, making it available for dedicated collectors. Nearby Piute County is another area in Utah with numerous obsidian sources. Originally the Wonder text referred to the contiguous United States those with touching borders but we updated it to clear things up!
We are undergoing some spring clearing site maintenance and need to temporarily disable the commenting feature. Thanks for your patience. Drag a word to its definition. You have answered 0 of 3 questions correctly and your score is:. Want to add a little wonder to your website? Help spread the wonder of families learning together. We sent you SMS, for complete subscription please reply. Follow Twitter Instagram Facebook. What is obsidian? How is obsidian formed?
What is obsidian used for? Tags: See All Tags earth , geology , obsidian , rock , science. Wonder What's Next? Try It Out We hope you enjoyed learning more about obsidian! Keep exploring by checking out the following activities with a friend or family member: Are you familiar with the many varieties of obsidian?
If you don't live in an area known for obsidian, you might not have ever seen obsidian up close in any of its varieties. No problem! Just jump online to check out Obsidian Gallery to see pictures of obsidian.
Which pictures interest you the most? Share what you learned with a friend or family member! Do you think it would have been easy to make ancient tools out of obsidian? Why or why not? What do you think they looked like? Jump online to check out Obsidian Tools to see some examples of ancient tools made from obsidian.
How sharp do you think these tools were? What might they have been used for? Are you up for a challenge? Pretend that you're an ancient settler living in your area. Think about what sources of food would be available to you.
What fruits and vegetables might you be able to grow? What animals inhabit your area? What tools would you need to survive? Now think about how you would go about making the tools you would need. What raw materials can be found in your area? If you want, take a walk around your neighborhood or a drive around the surrounding countryside.
What do you see? What can you find? Using what you can find on hand, try to make at least one example of a simple tool. Can you make an arrowhead out of a rock? What about an arrow out of a piece of wood? Have fun being creative and thinking like an ancient settler! Did you get it? Test your knowledge. Wonder Words atom lava trace rare razor deposit molten magma volcanic surface uniform artifact crystalline igneous obsidian extrusive conchoidal scalpel Take the Wonder Word Challenge.
Join the Discussion. Nadia Dec 10, This was very helpful for my project for school, Thank you very much! Ill be sure to use this website whenever I have another upcoming project! This was very understandable and kid friendly! This website game me all the information I need! Thank you!! Dec 14, Jun 30, Feb 1, I have many different fact to share with you 1. The most common color of obsidian is black. Obsidian can be found all over the world in areas with volcanic kind of activity.
Feb 2, Princess Chloe aka Chloe Feb 1, Hi Wonderopolis! Love you guys!! Keep up the hard work! Mailee Feb 1, This is an awesome thing to learn! Karter Oct 31, I think obsidian is a rock that is needed for stuff.
Nov 1, You're right, Karter! Obsidian is still used for jewelry and for surgical purposes! Colton Oct 27, Oct 28, Hello there, Colton!
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