“The shells of a sea creature, the mollusk Placuna placenta, are not only exceptionally tough, but also clear enough to read through. Now, researchers at MIT have analyzed these shells to determine exactly why they are so resistant to penetration and damage — even though they are 99 percent calcite, a weak, brittle mineral.”
Mineral hardness picks are pencil-like tools that have points made from materials that match the hardness of minerals in the Mohs Hardness Scale. With them you can easily test the hardness of mineral grains in a rock and test the hardness of small-size specimens. In our opinion they are easier to use than pieces of minerals and allow you to obtain more accurate results. They also do not contaminate your specimen with particles of the hardness mineral.
The Arizona Geological Survey has published Rare Earth Elements Deposits in New Mexico by Ginger McLemore in electronic format. It is from the Proceedings of the 48th Annual Forum on the Geology of Industrial Minerals, Phoenix, Arizona, April 30 – May 4, 2012.
“Some experts think that recycled rare earths from scrap materials and discarded products may eventually be able to meet up to 40 percent of global demand. That could be a boon for the U.S. and other Western nations, since China now dominates the world market for rare earths and can effectively control their supply and price.” Quoted from ScienceLine.org.
“It might be the ugliest diamond you’ll ever see, but within this brown sliver of carbon is a gem of a find for a University of Alberta scientist working to unravel an ocean-sized mystery deep beneath the Earth.” Quoted from the University of Alberta press release.
The Ontario Graphite mine is being reopened and management believes that it will become the largest graphite mine outside of China. Graphite economics have improved since the previous owner closed the mine in 1994.
Of all the minerals mined from the Earth, none is more useful than gold. Its usefulness is derived from a diversity of special properties. Gold conducts electricity, does not tarnish, is very easy to work, can be drawn into wire, can be hammered into thin sheets, alloys with many other metals, can be melted and cast into highly detailed shapes, has a wonderful color and a brilliant luster.
Although most gemstones are mineral materials, a number of organic materials and fossilized organisms are considered to be gemstones. The most common of these are pearl, bone, amber, coral, ivory, petrified wood, fossil coral, dinosaur bone and more.
Olivine is the name of a group of rock-forming minerals of Earth’s crust. It is usually found in mafic and ultramafic igneous rocks. It is also found in Earth’s mantle and in some meteorites. Although it is not often used in industry, gem-quality specimens are cut into a gemstone known as peridot.
Chrysoberyl is an extreme gem. At 8.5 on the Mohs Scale it is the third hardest gem mineral. At 3.7 to 3.8 it has a very high specific gravity for a non-metallic mineral. It is the gem with the finest cat’s eye. And, some specimens change color depending upon the type of incident light.
An interesting article on “Diamonds and the Geology of Mantle Carbon” that considers the various types of diamonds, their host rocks, inclusions, geographic distribution, environments of formation, age, trace element composition, textures, carbon/nitrogen isotopes, geobarometry, and lots more.
The Arizona Geological Survey just published a special episode of Arizona Mining Review. Lee Allison interviews Peter Megaw, Exhibits Chair of The 60th Annual Tucson Gem and Mineral Show which begins today. At least 40 other gem, mineral, fossil and jewelry shows have been occurring in Tucson for the past few weeks.
Peridotite is a host rock of chromite, a source rock of diamonds, a potential sink for atmospheric carbon dioxide and the rock that makes up much of Earth’s mantle. Did you realize it was so important?
A few minerals have an interesting physical property known as “fluorescence”. These minerals have the ability to temporarily absorb a small amount of light and an instant later release a small amount of light of a different wavelength.
A Nature article reports how some researchers believe that climate change can be mitigated by crushing olivine-rich rocks and exposing them to weathering – to take advantage of olivine’s ability to sequester carbon.
“A recent geological study indicates North Korea could hold some 216 million tons of rare earth minerals [...] if verified, the discovery would more than double global known sources and be six times the reserves in China, the market leader.” Quoted from the Voice of America article.
David Briggs has another article in the Tucson Citizen. This one on the supergene alteration and mineralization assemblages, which are formed when these sulfide-bearing deposits are exposed to near-surface, oxidizing solutions (groundwater) as they are exhumed by erosion and exposed to weathering.
“Potash is a non-renewable resource that is a key ingredient in fertilizer along with phosphate and nitrogen. Increased demand for fertilizers and potash has driven potash prices from US$96/tonne in September 1990, to US$203/tonne in July 2007, to US$495/tonne in April, 2012. A dwindling supply of arable land worldwide coupled with population growth requires increased food production from that land.” Quoted from the report.
They are called “anthill garnets” because they are found on and around the margins of anthills. The ants encounter the garnets while excavating their underground passages, haul them to the surface and discard them.
DonorsChoose.org is a website where K-12 teachers post projects that they would like to have funded and anyone anywhere can provide support. Many of these teachers would like to have materials to help them teach about rocks and minerals. Here are three projects that might appeal to you.
““Iris Agate” is a name used for a finely-banded agate that produces a spectacular display of color when it is cut properly and illuminated from a direction that sends light through its very thin bands.”
Labradorite is a feldspar mineral of the plagioclase series. Some specimens exhibit a schiller effect, which is a strong play of iridescent blue, green, red, orange, and yellow colors. Labradorite is so well known for these spectacular displays of color that the phenomenon is known as “labradorescence.”
“The Bureau of Economic Geology frequently fields calls from the general public to find information about clay deposits, uranium site locations, sand and gravel deposits, or what
resources, in general, are located at or around a specific location. The interactive Map provides the public with the means to search out locations on their own, and click on the points of interest, bringing up pertinent information…”
For more information about the map see the “Under the Radar..” section here.
“USGS scientists are reanalyzing rocks, minerals and associated mine tailing samples – some collected 120 years ago – to assess their rare and critical elements, which could become potential for economic development.” Quoted from the USGS press release.
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Homeowners Insurance usually does not cover damage caused by floods, landslides, earthquakes and other geohazards.
Frac Sand is a high-purity silica sand used in hydraulic fracturing to enhance the flow of oil and gas from tight rock units.
Diamonds from Coal? Diamonds form under a variety of conditions that rarely involve coal as a source of carbon.
Fluorescent Minerals glow with spectacular colors when illuminated in the dark with an ultraviolet lamp.
Helium is a byproduct of the natural gas industry. Its most important use is in magnetic resonance imaging (MRI) machines.