Taxonomy term


Mineral Resource of the Month: Antimony

Antimony is a lustrous silvery-white semimetal or metalloid. Archaeological and historical studies indicate that antimony and its mineral sulfides have been used by humans for at least six millennia. The alchemist Basil Valentine is sometimes credited with “discovering” the element; he described the extraction of metallic antimony from stibnite in his treatise “The Triumphal Chariot of Antimony,” published sometime between 1350 and 1600. In the early 18th century, Jöns Jakob Berzelius chose the periodic symbol for antimony (Sb) based on stibium, which is the Latin name for stibnite.

18 Jan 2015

Mineral Resource of the Month: Strontium

Strontium occurs commonly in nature, ranking as the 15th most abundant chemical element on Earth. Only two minerals contain sufficient strontium, however, to be used commercially to produce strontium compounds: Strontianite (strontium carbonate) has a higher strontium content, but celestite (strontium sulfate) is by far the most abundant strontium mineral.

24 Dec 2014

Bare Earth Elements: Past and present directors dissect the future of USGS

The U.S. Geological Survey, including its employees and leadership, have a penchant for self-assessment and an ambition for pragmatic self-improvement. That was on display Thursday, Dec. 18, in San Francisco in an hour-long panel discussion held in conjunction with the annual fall meeting of the American Geophysical Union, and featuring USGS acting director Suzette Kimball along with four of the five most recent past directors and acting directors. The panelists candidly addressed a number of issues, including how USGS has been and should continue adapting to best address its roles in science and public service, as well as internal and external barriers affecting its success in these roles.

22 Dec 2014

Mineral Resource of the Month: Mica

The mica mineral group includes 34 phyllosilicate minerals, all with a layered, platy texture. The mineral has been known for millennia: Mica was first mined in India about 4,000 years ago, where it was used primarily in medicines. The Mayans used it for decorative effect in stucco to make their temples sparkle in the sun. Today it is used in everything from electrical products to makeup.

22 Nov 2014

Mineral Resource of the Month: Vermiculite

Vermiculite comprises a group of hydrated, laminar magnesium-aluminum-iron silicate minerals resembling mica. They are secondary minerals, typically altered biotite, iron-rich phlogopite or other micas or clay-like minerals that are themselves sometimes alteration products of amphibole, chlorite, olivine and pyroxene. Vermiculite deposits are associated with volcanic ultramafic rocks rich in magnesium silicate minerals, and flakes of the mineral range in color from black to shades of brown and yellow. The crystal structure of vermiculite contains water molecules, a property that is critical to its processing for common uses.

16 Sep 2014

Mineral Resource of the Month: Selenium

Selenium, a relatively rare element with diverse uses, is widely distributed within Earth’s crust, but it does not occur in concentrations high enough to justify mining solely for its recovery. Selenium is recovered as a byproduct of nonferrous metal ore processing, principally from the anode slimes associated with electrolytic refining of copper. Slimes from primary copper refining can contain as much as 10 percent selenium, but are generally much lower.

12 May 2014

Mineral Resource of the Month: Wollastonite

Wollastonite, a calcium metasilicate, has an ideal composition of 48.3 percent calcium oxide and 51.7 percent silicon dioxide, but it can also contain minor amounts of aluminum, iron, magnesium, manganese, potassium, sodium or strontium substituting for calcium. Wollastonite occurs as prismatic crystals that break into tabular-to-acicular fragments. It is usually white but also may be gray, cream, brown, pale green, or red depending on its impurities and grain size.

14 Apr 2014

Mineral Resource of the Month: Talc

When people think of talc, they often think of talcum and baby powder. However, these uses of talc are minor compared to its use in industrial manufacturing. The leading use of talc in the United States is in the production of ceramics, where it is a source of magnesium oxide, serves as a flux to reduce firing temperatures, and improves thermal shock characteristics of the final product. Worldwide, the major use of talc is as a paper constituent, where it fills the interstices between cellulose paper fibers, reduces paper transparency, improves ink receptivity, and absorbs undesirable tree sap residues that can generate blemishes in the paper.

03 Mar 2014

Mineral Resource of the Month: Iron and Steel

Iron is one of the most abundant elements on Earth, but it does not occur in nature in a useful metallic form. Although ancient people may have recovered some iron from meteorites, it wasn’t until smelting was invented that iron metal could be derived from iron oxides. After the beginning of the Iron Age in about 1200 B.C., knowledge of iron- and steelmaking spread from the ancient Middle East through Greece to the Roman Empire, then to Europe and, in the early 17th century, to North America. The first successful furnace in North America began operating in 1646 in what is now Saugus, Mass. Introduction of the Bessemer converter in the mid-19th century made the modern steel age possible.

03 Feb 2014

Down to Earth With: Sally Jewell

Most people who find their way into public office start locally, perhaps by running for a seat on the school board or city council. Sally Jewell’s first foray into public service came at the behest of President Obama, who last year nominated her as the 51st Secretary of the Department of the Interior (DOI) — the first Secretary in more than a decade with a background in geoscience.

28 Jan 2014