Coal perspective

By Richard I. Gibson

My local paper today had a front-page article about record coal exports, at 125,000,000 tons for 2012. That’s a lot of tons, but it’s just 11% of the total amount of coal mined in the United States—1,094,000,000 tons in 2012, down a bit from the recent high of 1,172,000,000 tons in 2008. The US has produced more than a billion tons of coal every year since 1994. Exported coal first passed 100,000,000 tons per year in 1981, averaging around 80,000,000 tons a year since then.

The US is a distant second in coal production after China’s 3.9 billion tons a year, and well ahead of #3 Australia, which mines about 457,000,000 tons a year.

US coal consumption has decreased by about 25,000,000 tons a year since 2007 to just over 1 billion in 2011, largely because of increasing use of natural gas in electrical power generation. In the same period, China’s consumption increased from 2.8 billion to 3.8 billion tons per year, an increase equal to the total US annual consumption. It doesn’t take a rocket scientist to figure out that China is where the coal demand is, as it is for a great many basic commodities.

So it will also be no surprise to learn that US exports of coal, that 11% of total production, are also increasing to China, close to doubling from 2011 to 2012, from 5.6 million tons to more than 10 million tons (which amounts to 1% of total US production). China is now the third largest single recipient of US coal exports (after the Netherlands and the U.K.), up from the 8th position in 2011.

But by continent, Europe receives more than six times as much US coal as China does, with 66 million tons in 2012. The leading importers in Europe are Netherlands (13.5 million tons) and the U.K. (12.1 million). North American exports, at 11.4 million tons in 2012, mostly to Canada and Mexico, still exceed those to China. A comparable volume of US coal goes to South America, mostly to Brazil and Chile. In Asia, other leading importers of US coal are South Korea (more than 10 million tons in 2011, but just over 9 million in 2012) and India and Japan, at 6.8 and 5.7 million tons imported from the US in 2012, respectively.

Image credit: US government photo (public domain) of a Wyoming coal mine, via Wikipedia.

Gallium revisited

By Richard I. Gibson

In this post on gallium in March 2011, I said there was no limitation in sight to the increasing price of gallium. But I was wrong.

After five years of prices ranging from averages of $688 per kilogram (2011) to $449 (2009), gallium’s price plummeted to about $275/kg in October 2012. Why? The simple rules of supply and demand.

China ramped up its gallium production anticipating a rapid increase in use of gallium-based LED’s (light-emitting diodes) in back-lighting for computer and other electronic device displays, but the growth of that industry was much less than projected. Supply outran demand, and the price fell. China increased world gallium capacity dramatically, by about 35% in two years, while demand simply grew at a normal pace.

In the long run, gallium has a bright future, because of its critical use in smartphones, where ten times the volume of gallium arsenide is used over conventional cell phones. The likely slow but steady growth in CIGS (copper-indium-gallium diselenide) solar cells will also contribute to increases in gallium demand.

The $32-million US gallium industry relies almost entirely on imports from refineries in Germany (32% of imports), U.K. (27%), China (15%) and Canada (11%), a slight reorganization of sources from my 2011 post. Integrated circuits consume 71% of gallium in the U.S., with the other 29% going to solar cells, photodetectors, and telecommunications devices like smartphones.

Gallium in January 2013 was priced at about $280/kg.

The price of lead

by Richard I. Gibson

from Wikipedia Commons (public domain)

It will come as no surprise: the basic driver of the price of lead is automobile sales in China. Lead's price had been stable for quite a few years at about 20 cents a pound; but in 2004 it doubled to 40¢ then to 60¢ in 2005. World economy made it volatile in '08-'09 but it peaked at about $1.50 in 2007-2008. It has remained volatile since but floating around $1.00 per pound, still driven mostly by the lead-acid battery business and by China's 25%-a-year increase in auto sales (at least from 2006-10 with a small dip for the global recession in 2009).

In the US in 2011 86% of lead went to lead-acid batteries. China produces about half the world's lead but is still a net importer. U.S. production amounts to less than 8% of world total, but the US is a net exporter. Mine production totaled about 345,000 metric tons of lead in 2011, worth about $918,000,000. The vast majority of U.S. lead production comes from Missouri and the Red Dog Mine in Alaska. Consumption of lead in the United States runs to about 1,500,000 metric tons a year, five times the mine production; the apparent shortfall is made up from recycling which accounts for 83% of U.S. lead consumption.

As a consequence of the high price of lead, a friend of mine can make a good profit by making 4-ounce lead sinkers for high-end fishing expeditions.

from InfoMine.com

Could another Guano War develop?

A significant portion of Chapter 7 in What Things Are Made Of is devoted to phosphorus and phosphate rock, the building blocks of fertilizer and critical for life. The term “peak phosphorus” is only about four years old, but together with rare earths and lithium, global phosphorus supply is gaining mainstream attention.

While some research suggests phosphorus supplies could decline to problem levels by 2035, a recent analysis takes a different view. Either way, irregular distribution—one of the themes of my book—will probably impact phosphorus trade and use.

Phosphate rock ooids from Montana. Photo by Richard Gibson

In 2010, the U.S. imported 15% of its phosphate rock, the highest import dependency in history. The United States was a net exporter most years until about 1997, and imports were generally small until 2010, in part a reaction to the apparent ending of the global recession. All U.S. phosphate rock imports came from Morocco—the little country that owns or controls about three-quarters of the world’s reserves. Morocco and the U.S. produce about equal amounts, at 26 million tons per year (about 15% of world production each). China leads the world in phosphate rock mining with 37% of the total.

The mineral apatite, calcium phosphate, forms phosphate rock. Exactly how these deposits arise is still somewhat questionable, but upwelling ocean currents are thought to allow the chemical precipitation to occur. Other economic phosphate deposits are bird guano; islets off Peru covered with such material contributed to the “Guano War” in the 1860s. Whether demand for phosphate will lead to anything beyond trade wars remains to be seen.

Cadmium: batteries, TVs, plastics

Greenockite from Tsumeb, Namibia. 

Nobody mines cadmium. It comes from metal refineries, mostly zinc processors, where it is recovered as a trace component. It’s toxic, and not much goes a long way—only about 228 tons in the US in 2009 (down from 700 tons in 2005), with nickel-cadmium batteries (NiCd) leading the way. As lithium ion batteries, with greater energy density, take over in many small devices, NiCd batteries have declined in use, but they may return as storage batteries for on-grid solar energy systems that store electricity during the day and make it available at night.

China produces about a quarter of the world’s cadmium, and while the US is a net exporter, it ranks #9 in world cadmium production with about 4% of the total. A lot of US cadmium is exported to Asia where batteries are made.

Cadmium’s minor uses include photovoltaic devices such as photocopiers, where cadmium sulfide coats drums. Traditional uses include yellow, orange, and red pigments: yellow no-passing stripes on highways once contained cadmium. It also stabilizes plastics, makes lasers, and in phosphors gave the bluish tint to black-and-white TV sets in the 1950s. Cadmium was also once a low-melting component of solder and Wood’s metal—an alloy of bismuth, lead, tin, and cadmium sometimes used in the fusible valves found in automatic sprinkler systems. Wood’s metal melts at 158°F; when fires reach that temperature, the metal melts to open the valve, allowing water to flow.

The only noteworthy cadmium mineral is greenockite, cadmium sulfide, which forms pretty honey-colored crystals shaped like hexagonal barrels.

Photo by Christian Rewitzer, via Wikipedia under creative commons license.

Arsenic

Orpiment (arsenic sulfide)

Arsenic is Bad Stuff. It may have contributed to Napoleon’s death (accidentally or otherwise) and its presence in water supplies is an ongoing concern. For many years the wood treatment industry in the US consumed most of the arsenic used here, because it is an excellent preservative and insecticide. But toxicity issues led the industry to voluntarily cease using chromated copper arsenate for human-contact lumber like decks and picnic tables in 2003. Total US arsenic consumption has fallen from more than 30,000 metric tons in 1998 to 3,600 tons in 2009.

But arsenic finds its way into a lot of other critical but low-volume uses. It strengthens grids in lead-acid batteries, combines with other metals in some ammunition, and is a vital component of semiconductors in solar cells, circuit boards, and telecommunication electronics. Light-emitting diodes (LEDs) in computers, CD players, and numerous other household electronic devices contain gallium arsenide phosphide in tiny amounts. Two pounds of gallium arsenide can make 500,000 LEDs.

There are some arsenic ore minerals, mostly arsenic sulfides like lemon-yellow orpiment and red-orange realgar, but the primary ore is arsenopyrite, iron arsenic sulfide. It is also common in other minerals mined for elements like copper, and arsenic contributes significantly to environmental problems in copper-mining regions.

All US arsenic is imported. 86% of arsenic metal comes to the United States from China, which produces about half the world’s arsenic.

Orpiment photo from USGS via Wikipedia (public domain).

More about neodymium

One of the most common search words used by people who end up here is neodymium, the rare-earth element critical to powerful magnets in applications such as electric cars, wind turbines, and MRI machines. So I decided to write a bit more about rare earths and their worldwide occurrence.

Although rare earths are actually moderately common in the earth's crust, economic concentrations are indeed quire rare.

The Bayan Obo deposit in northern China, about 100 km from the Mongolian border, is presently the most productive mine complex for all rare earths. China produces 97% of the world's rare earths. Two North American deposits have recently attracted attention, because Americans are increasingly aware of our use and dependency on China for these elements (averaging 91% of U.S. imports), and because the price for some of the 17 rare earths is approaching levels to make mining them here economic once again.

The mine at Mountain Pass, in California’s Mojave Desert, was the largest rare-earth producer in the world until the 1990s when China took over. Molycorp, owner of the deposit there, has been processing accumulated ores for a couple years, although the mine itself has not reopened. And for final processing, they must ship their product to—you guessed it—China, the site of the only separation plant. Constructing one in the U.S. would be a huge investment, one nobody is presently willing to undertake.

Another promising undeveloped rare-earth deposit lies along and adjacent to the Continental Divide between Montana and Idaho, centered on the Lemhi Pass area. Two sites are held by U.S. Rare Earths, Inc., a private company.

The Idaho deposits were discovered and initially investigated in the late 1940s and 1950s because they held radioactive thorium, important in nuclear weapons development. The geologic setting is complex: igneous (formerly molten) rock bodies that were once thought to be part of the Idaho Batholith (around 100 million years ago, but with a wide range of dates) are now considered to be Mesoproterozoic (something like 1300 million years ago) in age, and to have metamorphosed (changed by heat and pressure) the surrounding rocks of somewhat older age. Sedimentary rocks of the Gunsight and Apple Creek Formations became quartzites and gneisses thanks to that metamorphic cooking. They also became the host rocks for the veins containing rare earths, gold, and other minerals.

The whole area is complicated further by thrusting – faulting, breaking rocks, by pushing older layers up and over younger layers, sometimes on scales of tens of kilometers or more, something that probably happened over tens of millions of years around 60-70 million years ago. Then, about 40 or 50 million years ago, Nature put a pile of volcanic rocks on top of the whole mess.

With all that going on, you can imagine that geologists are still working out the details, and what I write above is just a broad-brush overview. Some of the basic geologic mapping by U.S. Geological Survey, Idaho Geological Survey, and other scientists was published only a few years ago. It is not completely clear (at least not to me) when the valuable minerals came in—some indications say it was associated with the early metamorphic cooking, some suggest later. But the high grade of the ore at Lemhi Pass and near Salmon, Idaho, is clear, making the two sites perhaps the highest potential in the U.S. as undeveloped rare-earth resources.

Exploration and economic evaluation is underway for two other isolated rare-earth deposits, one near Sundance, Wyoming, and one beneath 600 feet of rock in southeastern Nebraska. Another potentially important North American rare-earth deposit is being investigated at Thor Lake, north of Yellowknife, Northwest Territories, Canada. We’ll save these possibilities for another post.

Cooking, cleaning, cooling

Fluorine is another relatively obscure element, but one virtually every American has in his or her home.

Fluorine gas derives mostly from the mineral fluorite—a beautiful mineral, prized by collectors for its multicolored cubic crystals. The Cave-in-Rock District, along the Ohio River in southern Illinois, once produced most of the world’s fluorite (also known as fluorspar). Those mines are closed now, and the U.S. is dependent on imports for 100% of the fluorspar that we consume, amounting to more than 400,000 tons each year.

Where does it go? Most fluorine goes to make hydrofluoric acid, critical in aluminum and uranium processing. And hydrofluoric acid is the feedstock for all fluorine-bearing chemicals, and this is where fluorine ends up in homes.

Teflon in non-stick cookware and Freon in air-conditioning systems are brand names for fluorinated compounds. Then there’s fluoride in toothpaste and municipal water systems, not as a communist plot but to alleviate tooth decay because fluorine in the crystal structure of calcium phosphate (the mineral making bones and teeth) is stronger than otherwise.

Enamel coating your stove almost certainly contains fluorine. Glass and steel manufacture demand it, as does cement production.

Where does the U.S. get fluorspar? Most imports (52% in recent years) come from world production leader China. Another 34% is imported from Mexico, with South Africa a distant third as a U.S. fluorspar supplier.

Photo of fluorite from Cave-in-Rock by Richard Gibson

The Latest Thing

I monitor various news, geology, and materials sources for hot topics to include in What Things Are Made Of. My latest discovery is a wonderful compound, copper indium gallium diselenide, with the unfortunate acronym CIGS.

Indium, gallium, and selenium often combine to generate light when electricity flows through them—variations on that list, often including arsenic, power lots of LEDs (light-emitting diodes) in all sorts of products from hand-held calculators to traffic signal lights.

Dow Chemical in Midland, Michigan, announced their brand of CIGS solar panels last October. They aren’t your traditional solar panels—these are thin films encased in plastic that can be embedded in asphalt shingles. Roofing contractors can install them—no need for specialized solar technicians. No offense to solar technicians, but this should make the panels cheaper to install. Dow hasn’t said what they’ll cost, but they should be on the market by mid-2010.

Indium forms few minerals, and most indium is a byproduct of zinc smelting. Indium supply follows the ups and downs of the zinc industry, which in turn depends largely on large-scale steel galvanizing. Industrialization in China and India, calling for more and more galvanized (zinc-coated) steel communication towers and highway barrier systems, isn’t the controlling factor behind zinc consumption, but it is an important aspect of it.

China leads the world in indium production, and also leads in supplying imports to the United States which is 100% dependent on foreign sources for indium. Likewise, virtually all gallium used in the U.S. is imported, in almost equal proportions from China, Ukraine, Germany, and Canada. Processing bauxite to produce aluminum yields most of the world’s gallium. Selenium is also a byproduct, usually of copper refining. One refinery, ASARCO’s 11-acre building near Amarillo, Texas, produces all primary domestic selenium, but the U.S. also imports nearly 600 tons per year, mostly from copper refineries in Belgium.

Some estimates suggest that indium demand could increase ten-fold over the next five years because of increased CIGS solar panel usage. If that happens, look to China for supplies—China produces 58% of the world’s indium, far ahead of #2 Japan (11%). You don’t care about solar cells? How about your flat-panel TV, computer screen, iPod, and other display devices? They all require indium.

Flat-panel image from Wikipedia, under GNU Free Documentation License.

American dependency on natural resources

Many people I talk to have the mistaken impression that the United States is not only self-sufficient in most resources (with the generally known exception of oil), but that we are also the world’s 600-pound gorilla when it comes to most of the important natural resources we use. Not so.

In the list below, I’m focusing only on some of the main mineral resources, things that are familiar to most people. For each commodity, I’m providing the world production leader (in some cases, a very close #2 is also given) with the percentage of world mine or factory production that nation contributes, using 2008 figures from the US Geological Survey. U.S. percentage and world rank is given for comparison. For most of these resources, the U.S. consumes far more than it produces.

Aluminum (smelter): China (33%). US= 7%, #4
Cement (plant): China (50%). US= 3%, #3
Copper: Chile (35%). US= 8%, #2
Gold: China (13%). US= 10%, #3
Iron Ore: China (35%). US= 2%, #7
Raw Steel (foundry): China (38%). US= 7%, #5
Lead: China (40%). US= 12%, #3
Manganese: South Africa (21%), China (20%). US= none
Molybdenum: USA (29%, #1), China (28%)
Nickel: Russia (17%). US= none
Silver: Peru (17%). US= 5%, #7
Sulfur: USA (13%, #1)
Tin: China (45%). US= none
Tungsten: China (75%). US= est. 1%, est. #14
Zinc: China (28%). US= 7%, #4

My point is simple: Isolationist attitudes about natural resources are untenable. Modern society, especially in the United States, relies on a thoroughly globalized interdependency—whether we like it or not.

Who cares about neodymium?

You should. It’s in your CDs and CD player, computer hard drive, TV tube, sunglasses, and cigarette lighter flints. It helps lasers speed communications through fiber optic networks. Neodymium magnets are critical for MRI scanning devices. Loudspeakers, headphones, guitar pick-ups, model airplanes, welder’s goggles all have some. Geologists and astronomers use neodymium and its isotopes to understand the universe around us. But as Americans become more concerned about the price of gasoline and its availability, it is in electric car motors that neodymium makes news.

A typical Prius contains two pounds of neodymium, mostly in magnets that help drive the motor. Where does it come from? Virtually all the world’s neodymium comes from one location: the Bayan Obo Mine in northern China. You can see the mine in Google Earth by searching on "Bayan Obo, Baotou, Inner Mongolia, China"—the mine is north of the city. China’s virtual monopoly—and trust me, they know what they have—on this and other rare-earth elements has some car makers worried, enough so that they’re exploring arrangements with Viet Nam and other nations that have smaller, undeveloped supplies of these critical elements.

The U.S. was once the largest producer of rare-earth elements, mostly from one mine in California’s Mojave Desert. But China’s vast reserves catapulted it into first place in 1992, and pretty much put that mine out of business in the late 1990s. The U.S. has had no primary mine production of rare earths since 2002, and imports, 87% from China, account for all our consumption today. The mine at Mountain Pass is mothballed, but prices and worries about supply are encouraging the owners to explore the idea of re-opening it.