When it comes to medications and preserving your health, there are always bitter pills to swallow, Bill Langer writes. This is especially so when they’re laced with barium sulfate.
I am intimately familiar with a mineral called barite, aka barium sulfate.
This is because I recently underwent a computed tomography (CT) scan that used X-rays to make detailed pictures of the inside of my mid-section. X-rays pass right through the skin and soft tissue so I prepared for the CT by drinking a barium sulfate ‘smoothie’.
Ultra-pure barite works great for CTs because barium has a high atomic number of 56, which is the number of protons and electrons in the atom. When X-rays go through barite they interact with the cloud of electrons around the barium atoms and the barium electrons stop the X-rays. Also, barite is uncommonly dense, so it packs more protection into a smaller volume.
The poorly flavoured, finely ground barium sulfate-water mixture travelled down my throat, into my stomach, through my intestines and ultimately out the ‘back passage’. The barium sulfate coated the lining of the digestive tract so the doctor could see if anything was wrong inside me.
The specific gravity of barite is 4.5g per cubic centimetre, about twice that of most common industrial minerals. Indeed, the name barium comes from the Greek barys, meaning ‘heavy’. The high density of barite makes it indispensable for the oil and gas industry where it is ground up and added to drilling mud to help counteract the high pressures encountered while drilling deep wells.
Doctors and well diggers love barite because it is non-reactive. It just sits there counteracting pressure or impeding X-rays. Even in the stomach or intestines, which are designed to digest stuff, it just passes right on through.
Obviously a whole lot more ground up barite goes into drilling wells than into barite smoothies. The US used 3.3 million tonnes of barite in 2012. The many other uses for barite include filler in paint, plastics and rubber, powder coatings, automotive brake pads and heavy aggregate for radiation shielding concrete. Even so, 95 per cent of barite went into well-drilling.
About 80 per cent of the barite consumed in the US is imported, mostly from China. Many importers ship barite from China to Gulf Coast ports, where most of the barite grinding mills are located.
That ground barite is shipped to off-shore drilling operations in the Gulf of Mexico or on-shore operations in Louisiana, Oklahoma, and Texas. Most barite mined in the US comes from Nevada, is ground in Nevada or Wyoming and is sold to petroleum-drilling customers in Colorado.
Barite commonly is shipped by freighters in lot sizes greater than 50,000 tonnes. At times suppliers cannot acquire that much high quality barite, so they add lower quality barite to the shipment. This results in inconsistent product quality that must be addressed at the US mills. Ocean freight rates are high and congestion in Chinese ports causes delays.
Accidents and deaths in China’s mining industries have prompted the government to enforce regulations more comparable to US regulations. China is keeping more barite for its own uses and some local and regional authorities have reduced production from mines.
All these factors, as well as others, drive up prices. For example, the price per tonne of barite loaded on a ship in China was about $USD72 to $USD75 in October 2010 but had doubled to $US146 to $US158 by October 2012.
This is just a taste of the barite industry. It’s a pretty complicated business, and something tells me it is not going to get any simpler. I feel it in my gut.
Bill Langer is a consultant geologist. Email email@example.com or visit researchgeologist.com