Energy companies in North America use a silica crystal during hydraulic fracturing, or fracking, operations. The practice involves water mixed with the fine particles and trace amounts of chemicals to create fissures in shale that release trapped oil and gas deposits.
Companies mining the sand are growing, though there's been a backlash against their operations. Last week, the Minnesota Department of Natural Resources ordered a mine operator to shut down because of environmental concerns.
The Price of Oil, a group critical of the oil and gas industry, said there have been corresponding health concerns with so-called frac-sand. The fine silica sand mined for fracking can cause lung damage, it said.
The group said Wednesday the outcry over fracking now extends to sand, which should serve as "a warning to countries such as the U.K., which recently opened up half their country to fracking."
The British shale industry is in its infancy, though the government said natural gas from shale could provide a source of economic stimulus and energy security.
2014: The Year in Music [PHOTOS]