About the blog: What Things Are Made Of

AMERICA'S GLOBAL DEPENDENCY FOR NEARLY EVERYTHING


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.


Obviously this blog hasn't been updated in years. If you are interested in follow-up posts on this (and other) topics, please visit my Substack page.



Showing posts with label stone. Show all posts
Showing posts with label stone. Show all posts

Tuesday, January 31, 2012

Mineral production up in 2011

To the extent that mineral production reflects the economy, it looks like things were improving in 2011. The US Geological Survey released its 2012 Mineral Commodities Summaries, covering 2011, and most metals show significant increase in value.

Gold and copper are usually the leading metals by value produced in the US. In 2008, thanks to low gold prices, the copper industry yielded ore worth half again the value of gold: $9.4 billion vs. $6.7 billion for gold. Copper depends sensitively on the building industry, and with the recession in 2009, its value fell to $6.2 billion while gold held relatively steady at $6.4 billion.

In 2010, the copper business was worth $8.4 billion and gold was at $8.9 billion, but with continuing increases in gold’s price, in 2011 gold was valued at $12.2 billion, surpassing copper’s record value of $10 billion.

Other 2011 commodity business values include iron ore at $6 billion (triple the 2009-2010 amount) and the titanium dioxide industry, at $3.8 billion, surpassing its 2008 rate of $3.7 billion for the first time.

The most valuable non-fuel mineral commodity produced in the U.S. has been crushed stone, holding steady in 2009-2011 at $11 billion, more valuable than gold, copper, or any other metal, but gold took the lead in 2011 for the first time in recent years.

Despite the surge in value for gold produced in the U.S., the nation went from a net exporter of gold to a net importer in 2010-2011, with about 38% of consumption imported. Much of this was raw ore for processing. Copper imports have been fairly steady for the past 5 years at about one-third of total consumption (35% of our copper was imported in 2011).

Monday, November 8, 2010

Sandstone facades

Buildings are built of many things. What Things Are Made Of has one chapter about simple home construction and another including monuments and office buildings. I’m involved in planning for the Butte-Silver Bow Courthouse Centennial, coming up in 2012. It’s a huge Beaux-Arts creation whose cost was comparable to that of the Montana State Capitol in Helena.

The first floor façade’s rectangular panels boast uniform, fine-grained gray sandstone. A close look (or better, a careful look from a certain distance) reveals the sandstone’s beds to be angular, curved—not the expected planar laminations. The arrangement is called cross-bedding, crosscutting layering that means the sand was deposited in active rivers. The beds are essentially little sand dunes, channels, and other river-bed forms carved by flowing water.


The sand solidified into sandstone about 78 million years ago near what is now Columbus, Montana. Quarrying there began about 1890. Under the leadership of stonemason Michael Jacobs, born Jacobucci in Italy, the Montana Sandstone Company provided facing stone to numerous buildings in Butte, but it was the contract for the Montana State Capitol that put the company on the map and established Jacobs’ fame and fortune.

Today, stone decorating buildings is called dimension stone, and 78% of that used in U.S. construction is imported, with Brazil, Italy, China, and Turkey supplying nearly equal amounts. Brazil, China, and Italy provide mostly granite and Italy is also a major source of marble. Imported stone was worth $1.5 billion in 2009, compared to $377 million for domestic products. The U.S. is the largest consumer of these materials in the world.

Thursday, January 28, 2010

The most valuable mineral commodity

Before you read on, take a guess. What non-fuel mineral commodity adds up to the most valuable mineral industry in the United States? “Non-fuel mineral commodity” means minerals, metals, rocks, natural mineral-rich solutions, stuff taken from the earth other than oil, natural gas, and coal. And not water.

Here’s a hint: it’s not iron ore, not lead, not gold. It’s not silver, aluminum, or copper.

The most valuable mineral commodity was worth more than $13 billion in the U.S. in 2008, but its average price was just $8.98 for a ton. We used almost 1½ billion tons of this common stuff, and had to import a bit (just 2%) of what we used, mostly from Canada, Mexico, and the Bahamas.

Every state produces it, from more than 4,000 sites operated by more than 1,600 companies employing more than 80,000 workers. Texas, Pennsylvania, and Missouri are the top three producing states.

This most valuable material declined in use by a third from 2006 to 2009, a statistic that may suggest that its uses relate to factors affected by the recession. Indeed, the greatest use reported for the commodity is in construction, mostly road construction and repair. What is it? Crushed stone.