The Increasingly Invaluable Role of Metals on Civilization’s
onstant Quest for Freedon from Self-Reliance!
By G. Miles Lehman
A hallmark of mankind’s technological development through the ages is his penchant for recognizing and exploiting the inherent qualities of various elements, predominantly metals, to ease the rigors of daily life. The Bronze Age (circa 4000 years BC), Iron Age (circa 1200 years BC) , and the Industrial Revolution (roughly 1760 to 1840) are well-recognized appellations for eras marking great leaps in urban civilization that simply could not have occurred without metallurgical knowledge and utilization. An argument can be made that we are now immersed in the “High Tech” Age!
Components for the very things we can’t seem to live without—yet take so much for granted—such as computers, cell phones, calculators, iPods and iPads, tablets, ad infinitum, are so dependent on a virtual litany of elements, both common and rare, that without their exploitation our daily endeavors today would be drastically more self -reliant. Who hasn’t witnessed the cashier who could not calculate change without consulting the register for the answer?
Though by no means exclusive, most of the elements we absolutely rely on today are metals, which comprise nearly 80% of all known elements. Metals are elements on the Periodic Table that share specific and readily recognizable characteristics. With some notable exceptions, they are malleable (can be flattened out by pounding), ductile (able to be drawn into a wire), solid (mercury is liquid at room temperature), exhibit a metallic gray or silver luster (gold and copper notwithstanding), and possess a high electrical and thermal conductivity. Those with a negative standard reduction potential (easily oxidized, in layman’s terms) are only found in a combined state, such as iron oxide (rare exceptions include meteorites and a small deposit of native iron in Greenland) and zinc sulfide. Those with positive reduction potentials may occur in the native state (e.g. gold, silver, copper).
What would our lives be like today without aluminum for cars; titanium for airplanes; copper for electrical components; nickel for stainless steels; lithium in batteries? Besides well-known ornamental and monetary uses, gold finds essential use in corrosion-resistant electrical connections in all types of computerized devices. Silver, once the foundation of the photography industry, now finds new employment in solar panels, water filtration, and electrical contacts. Platinum is a vital constituent in catalytic converters. Magnesium, obtained mostly from seawater, is used in lightweight structural alloys for such things as ladders and aircraft parts.
These are just the better-known elements, which are hardly alone in their place in the technological revolution. Technology is also dependent on more exotic and far less well-known elements. For example, electrode planes made of indium-tin oxide are essential components in Liquid Crystal Displays used in laptop computers, digital clocks and watches, microwave ovens, CD players, et al. In fact, our technological prowess is growing increasingly dependent on an entire class of metals known as the rare earth elements (REEs).
Not necessarily as rare as the name implies (cerium is almost as abundant as copper), REEs are very similar to each other in chemical reactivity. Due to the electron configuration in their outermost shells, these f-transition metals are grouped together in the “Lanthanide” and “Actinides” series on the Periodic Table. While some opinions consider only the lanthanides to be rare earths, chemistry textbooks traditionally treat both series together as REEs, which is preferred by most scientists. Ironically, lanthanum and actinium are not actually in their namesake categories, as they are properly considered d-transition, not f-transition, metals.
Lanthanides, all of which occur naturally, encompass elements with atomic numbers (quantity of protons in the nucleus) from 58 to 71. By contrast, most actinides do not occur in nature, existing fleetingly in nuclear experiments conducted only since the early 1940s. These elements have from 90 to 103 protons in their nuclei, and all are radioactive. Of these, uranium is the largest and best-known naturally occurring atom (92 protons). Many rare earths have interesting and innovative commercial importance.
Cerium alloyed with iron is the “flint” employed by cigarette lighters; praseodymium and neodymium are used in sunglasses and goggles for glassblowers; europium and yttrium are found in the red phosphor components of color TVs; thorium nitrate, in gas mantles in lanterns and street lamps; samarium alloyed with cobalt, to make high-strength permanent magnets used in micromotor tape drives in audio-cassette players, lightweight headsets, and to produce greater energy-efficiency in electric motors; europium, yttrium, cerium, and terbium in phosphors used to simulate natural daylight conditions and reduce energy consumption in fluorescent lamps. These are just some of the many esoteric applications for REEs.
The demand for the so-called rare earth metals has increased exponentially in recent decades, but economically minable deposits are growing increasingly depleted. Originally, REEs were derived from placer deposits in India and Brazil. After 1948, veins containing REE-bearing monazite discovered in South Africa claimed the top spot on the global market, lasting through the 1950s. Soon after, deposits first discovered in 1949 at Mountain Pass in San Bernardino County, California, supplied the exigency for REEs in response to increased demand for europium used in color TV screens. From 1965 to 1995, the Mountain Pass Mine operated by the MolyCorp mining corporation was the world’s leading supplier of REEs. External pressures forced the mine to close in 2002.
Since 2010, extensive deposits in China have reigned supreme, producing 95% of the world’s supply. Many mines around the globe had closed in response to China’s undercutting of prices in the 1990s to unfairly corner the market in REE exports under the guise of environmental protection. On August 29, 2014, the World Trade Organization ruled that China had broken free trade agreements, forcing the country to lift its restrictions. Consequently, former locations around the world resumed operations, most notably the one at Mountain Pass, which reopened in 2012—after lengthy renovation and upgrading of equipment and processing facilities—in response to concerns that the US would become completely reliant on China for components essential to the Defense industry!
Resources for imperative metals, however, are not limitless (copper, especially, is so widely used that it is becoming increasingly scarce; the U.S. Bureau of Mines estimates that the currently known worldwide reserves will be exhausted sometime this century!). However, new reserves—and new technological advances to exploit once uneconomical deposits—are being discovered. A 2011 study by Yasuhiro Kato at the University of Tokyo, for example, indicates potential large reserves in oceanic mud near hydrothermal vents.
Nevertheless, immediate attention should be granted to conservation over discovery, which entails recycling, such as the current examples of aluminum (from soda cans), lead (from car batteries), and copper wiring; and substitution where practical, utilizing glass, wood, environmentally friendly plastics, granite rock, etc.
Ultimately, however, we must turn our attention to more long-terms goals. Interestingly, our greatest—yet least recognized—resource is our oceans, in which nearly all elements can be found! Most are currently present in economically unfeasible concentrations. However, as extraction technology improves, and prices of the elements rise sufficiently, undoubtedly more and more elements can be obtained from the seas, which have such vast volume that they can be considered to have virtually an inexhaustible supply of most elements!
Imagine the wealth of gold, silver, copper, and other such precious elements dissolved in our vast oceans. With improved development of new, cheap, and abundant sources of energy (e.g. wind, solar, tidal, nuclear, etc), the future could see the economic possibility of mining many elements from the very substance that laps at our feet at the seashore, elements that today are tauntingly out of our reach. With responsible exploitation, there is no reason not to expect technological advancement to continue on its frenetic pace well into the future.
Of course, it still won’t hurt to be able to perform simple mathematical calculations without the help of a calculator.