Where is obsidian found

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. A detailed map will be needed to determine which of these lands are privately owned, federally owned, or under the direction of the BLM.

Clear varieties of obsidian contain very few opaque impurities or microscopic mineral crystals. Red or brown obsidian generally results from tiny crystals or inclusions of hematite or limonite iron oxide. Abundant, microscopic crystals of minerals like magnetite, hornblende, pyroxene, plagioclase and biotite, combined with tiny fragments of rock, likely produce the jet-black varieties of obsidian.

Microscopic crystals of various types of feldspars may yield the unique blue, green, purple or bronze colors associated with rainbow obsidian.

The reflectance of rainbow obsidian is likely attributed to a preferred orientation of microscopic crystals of feldspar or mica oriented along flow layers. A certain amount of water always is present in obsidian.

Very small inclusions of water vapor in the form of bubbles often are trapped in the glass. Tiny gas bubbles that have been stretched nearly flat along the flow layers in obsidian generally cause the reflectance of gold sheen and silver sheen obsidian. Some of these bubbles are visible to the naked eye. The bubbles can be seen readily with a strong magnifying glass or a microscope. Obsidian is relatively unstable from a geologic perspective.

It is rare to find obsidian older than about 20 million years, which is very youthful in comparison to most continental rocks that form the Earth's crust.

Over a long period of time, obsidian gradually changes from glass to rock in a process known as "devitrification. The "snowflakes" in snowflake obsidian are quartz crystals that have formed through devitrification of the original obsidian.

The crystals that develop through devitrification cause obsidian to lose its conchoidal fracture and glassy texture. Native Americans discovered almost all of the obsidian locations in North America. Each obsidian source area has a unique assemblage of trace elements, allowing identification of the original source locality for the obsidian used in prehistoric artifacts.

Trace element analyses have shown that native peoples traded this valuable commodity many hundreds of miles from the volcanic source areas along numerous trade routes. The fact that obsidian was transported great distances attests to the mystique of this unique material. My favorite place to collect obsidian is Glass Buttes in central Oregon. A trip to Glass Buttes is well worth the effort for the natural scenery, abundant and beautiful gem-quality obsidian, and exploration of a fascinating geological area.

These sagebrush- and juniper-covered hills are remote but accessible by automobile. Located in central Oregon south of Highway 20 and about 80 miles east of Bend, a visitor will be rewarded with many different varieties of obsidian through exploration of the area.

Fist-sized pieces are abundant and can be collected with no digging. For large pieces of high quality obsidian ranging up to several hundred pounds , considerable effort with a shovel and pry bar are necessary.

Further information on Glass Buttes can be found in several rockhound guidebooks that include the central Oregon area. Examples of obsidian from Glass Buttes and stone tools made from those materials by the author are included with this article.

Several varieties of obsidian from Glass Buttes, Oregon and tools made by the author from those materials. From left to right across the top, the obsidian varieties are silver sheen, midnight lace, pumpkin and red mahogany.

Collecting from road outcrops and cliff faces is not only illegal, but also very dangerous. Be sure to wear proper gear and always get permission to be on that site. Go collect! Because obsidian is easy to break like glass , collecting samples from an outcrop is relatively simple.

A good rock hammer will easily break large chunks of volcanic glass into small, usable pieces. However, make sure to bring a good collection bag because obsidian tends to be quite heavy. Use a rock and mineral identification guide to check the rock type in the field, such as those published by the National Audubon Society.

Laura Wormuth has been a professional writer for over five years and is currently the communications manager for Cambridge International. She holds a bachelor's degree in magazine journalism and a master's degree in earth sciences, both from Syracuse University. Things You'll Need. How to Find Agates. Facts About Geodes. How Is Labradorite Mined? How to Find Geodes in Idaho. Places to Find Flintstones.