About the blog: What Things Are Made Of


The United States relies on imports for dozens of commodities in everyday use. Often enough, that reliance is 100%. In this book I aim to provide awareness of the hidden geology and mineralogy behind common things, and to develop an appreciation for the global resource distribution that underpins our society. While concerns about oil import reliance are in the news every day, our needs for other minerals are comparable and are typically unknown even to technologically aware Americans.

Friday, May 28, 2010

The oil leak

Current (late May 2010) estimates of the rate of leakage in the Gulf of Mexico well are 12,000 to 19,000 barrels a day. Pretty bad, and significantly worse than early estimates.

With total U.S. oil consumption at 19,714,000 barrels a day (May 21, 2010), the leak at 15,000 barrels per day would take 1,314 days (more than 3½ years) to equal one single day of U.S. oil consumption.

The point is not to belittle the disaster—it's an awful thing—but rather to point out the gargantuan scale of U.S. oil consumption.

Tuesday, May 11, 2010

Offshore oil

In the wake of the disastrous oil leak in the Gulf of Mexico, visitation to my website’s oil pages has spiked to over 1000 unique visitors a day, as it does when the price goes up or hurricanes or wars interrupt our guzzling. There is plenty of information out there, so I see no need for me to expound on much about the problem. But I need to address one issue, the demand from some that we put an end to offshore drilling and production because it is so dangerous.

I’m as much or more of an “environmentalist” as many are. Most geologists are, because they love the earth. That does not mean we reject the value of earth products, whether oil or copper or neodymium. But those who would eliminate offshore oil exploration and production need to realize one thing.

More than a third (37% in December 2009) of U.S. domestic oil production comes from offshore wells.

Federal offshore areas (mostly in the Gulf of Mexico) produce more oil than any state. More than Texas, more than Louisiana, more than Alaska. More than 2,000,000 barrels a day in December 2009. Shut it off – and replace it how? There is no replacement source that can be tapped economically, if at all. By the time any new discoveries come onstream, in seven to 15 years from now, existing production will have declined by that much or more: we will only maintain the status quo if (IF) we discover and develop that much production. The only significant possible locations for those high-volume discoveries are offshore, and there is no guarantee that it exists at all.

To quote a fine summary (available here), “America simply doesn’t get it.”

Public domain image of offshore platform. Credit: NASA.

Friday, May 7, 2010

The kitchen floor

Last night I went to a Butte history talk focusing on home furnishings about 1910. Among the multitude of state-of-the-art items anyone could buy at Butte’s Hennessey’s store using the newly invented time payment plan (a.k.a. credit) was linoleum flooring.

Invented in England in the late 1850s, linoleum's basis was solidified linseed oil derived from flax plants. It gave a tough but flexible material. Minerals extend and improve the properties: finely ground limestone or whiting may comprise a third of linoleum’s volume while clays add flexibility and also serve as extenders or fillers.  Various other additives—sawdust, gum, pine rosin—also help give linoleum its desirable properties.

An unusual mineral, wollastonite, calcium silicate, crystallizes as tiny elongate needles or blades. This geometry helps bind other materials together, and as tough little bars, wollastonite makes linoleum stronger while maintaining its flexibility. It’s a chemically stable mineral that helps linoleum resist chemical attack and cracking over a wider temperature range than wollastonite-free material.

Although wollastonite deposits were exploited in Inyo, Kern, and Riverside Counties, California, from 1930 to 1970, the largest wollastonite mines in the U.S. are in Essex County, New York, in billion-year-old rocks of the Adirondack Mountains. The ore is processed at Willsboro, and together with another mine in Lewis County makes wollastonite New York’s fifth most valuable non-fuel mineral product. Almost all U.S. wollastonite production today comes from New York, adding up to about a quarter of all produced in the world. That ranks the U.S. at #3 for wollastonite, following China and India which together account for about 70% of world production.

Thanks to the New York mines, the U.S. is largely self-sufficient in wollastonite production, with something like 5% of consumption imported. India is the leading source of those imports, but China, Canada, Germany, Finland, Japan, and France also ship small volumes to the U.S.

Wollastonite finds its way into ceramics, metallurgy, paint, plastics, caulking compounds, friction products such as auto clutches and brakes, and synthetic rubber including auto tires.

Much “linoleum” today is really polyvinyl chloride, made from natural gas and salt. Although Frederick Walton patented his linoleum-making process in 1860, he failed to trademark the name and lost lawsuits alleging others who used the word infringed on his trademark. Consequently, “linoleum” is considered the first product name to evolve into a generic term—and it happened just 14 years after its introduction.

Wollastonite specimen image from U.S. Geological Survey via Wikipedia.

Sunday, May 2, 2010

Say – can you see?

An alchemist’s cabinet could have been the resource for modern eyeglass manufacture. The lenses contain a wealth of trace elements to improve their optical properties, from lanthanum (a rare earth, most of it mined in China today) to improve the refractive index and reduce color dispersion, to silver chloride or silver bromide in photochromic lenses that darken when exposed to ultraviolet light (UV).

Cerium, titanium, neodymium, and manganese in glass all help absorb harmful UV rays. Coloring and the non-reflective surface on sunglasses may contain erbium, one of the four rare-earth elements named for Ytterby, Sweden.

As with most glass, the fundamental component is high-purity silica, SiO2 – quartz, the most common mineral in the earth’s crust. Plastic lenses are polycarbonate petroleum derivatives. Such plastics may also form the frames and earpieces, but the nose pads are softer plastic, often rubber-like silicones. Silicones are complex organic-silica compounds typically synthesized from methyl chloride (usually derived ultimately from natural gas or petroleum, and salt (NaCl) to give the chlorine) in the presence of copper as a catalyst.

Metal frames, usually some alloy of steel, can include aluminum, magnesium, titanium, and other elements added for tensile strength, light weight, and other properties. Nickel or chromium coatings give varied appearances as well as corrosion protection. “Memory metal,” which springs back to its original shape after flexing, is one of several copper-zinc-aluminum-nickel or nickel-titanium alloys.

The inventor of the first eyeglasses is unknown, but early Renaissance Italy, a hotbed of innovation, is the likely location where some lucky resident wore the first spectacles. Old manuscripts suggest that convex lenses – barely more than frame-mounted magnifying glasses – began to correct farsightedness in the late 1200s; not until 1451 did Nicholas of Cusa, a German Catholic bishop, learn how to use concave lenses to combat nearsightedness. Benjamin Franklin invented bifocals in 1784, and George Airy’s astigmatic lenses provided correction for the last of the major eye focusing problems in 1825, a decade before Airy was appointed Britain’s Astronomer Royal.

George Airy (1801-1892) is better known (at least among geophysicists like me) for his determination of the earth’s mean density when he was only in his 20s. His pendulum experiments led to the Airy Hypothesis of isostasy, which says that mountain ranges must have root structures of lower density than the surrounding rock, proportional to their height.

Image: The 'Glasses Apostle' in the altarpiece of the church of Bad Wildungen, Germany. Painted by Conrad von Soest in 1403, the 'Glasses Apostle' is considered the oldest depiction of eyeglasses north of the Alps. Image in public domain via Wikipedia.