TVA, quartz and computer chips. What do they have in common with the digital revolution? Without TVA you might not be reading this article—or anything else—on your laptop, iPad or mobile phone. Learn more.
In the sleepy little corner of northwest North Carolina, during the 1940s, every miner worth his salt would tell you that quartz was virtually worthless. It was the byproduct of mining the more useful mineral feldspar. The quartz matrix was something to be gotten out of the way, and the quicker the better.
But that nuisance quartz would change the world, thanks in part to a team of TVA engineers who moved into the area and developed a method of mining that would revolutionize that industry and pave the way for another.
“Had TVA scientists not gone in there and developed froth flotation we might not have cell phones and lap tops—or computer chips at all today,” says Vince Beiser, author of the new book “The World in a Grain: The Deadly Global War for Sand.”
Wait—what? Read on.
“Miners in that part of North Carolina at the time were after feldspar,” says TVA historian Pat Ezzell. “It was used then in the production of glass, tile, electric insulators and other ceramic building materials.”
By the middle of the decade, TVA engineers had moved into the region to help invigorate the feldspar industry, carrying on minerals development work that had been ongoing at the agency from the time of its founding.
Their goal, as laid out in TVA’s 1946 Annual Report, was “exploring the possibility of lowering output cost and improving quality by adding feldspar flotation plants to present equipment.” The effort would be important, the report noted, as “about 30 percent of the Nation’s ground feldspar is produced in the Tennessee Valley area.”
Jumpstart the feldspar industry, the thinking went, jumpstart the local economy—right in line with TVA’s economic development mission. “TVA had the electricity to use the region’s environmental resources to jumpstart the feldspar industry, and thus the local economy coming out of WWII,” Ezzell says.
During the course of their work, the engineers developed a unique process of froth flotation, which effectively separated feldspar from quartz. (A patent for the process was awarded in 1953.)
Beiser describes the process: “You start by dumping crushed minerals into big tub, you mix in water to create a slurry and add chemicals called reagents, which are chemicals that stick to the minerals you don’t want and make them hydrophobic—repelled by water.
“So you have bits you’re trying to get rid of, then you pump air through that water and the bits you want clamp onto the air bubbles and rise top, creating a froth. And you skim off that froth and you’ve extracted that particular thing.”
In this case, feldspar. The thing you don’t want—in this case, quartz—drops to the bottom. And you dispose of it.
Or do you?
Turns out that in one little pocket of North Carolina, the tiny town of Spruce Pine, the quartz is the “purest naturally occurring quartz found on Earth,” according to Beiser. Not such a big deal in the 40s—but a great big deal today. Today, that Spruce Pine quartz is integral to producing the computer chips that make our world go ‘round.
“To make semiconductors you have to have completely pure silicon; you take sand and you put it through a number of chemical and industrial processes until you’re left with pure silica,” Beiser explains. “And you can’t just melt that stuff down in any old pot—you have to melt it down at high heat in a container that won’t react with it.”
What would make such a container? Quartz.
Spruce Pine quartz—mined mostly by a company called Unimin—is the number one and possibly only quartz used to create the crucibles that are used in creating that pure silicon, according to Beiser.
The science of froth flotation TVA engineers developed is still relevant in the mining industry, still separating the valuable mineral—now the quartz used to power the digital age—from the dross.
Read an except from Beiser’s new book in Wired magazine.