Image copyright Getty Images Image caption An open pit mine in Kolwezi, Democratic Republic of Congo, where cobalt and copper is extracted 
 
 Gold once lured prospectors to the American west - but now it's cobalt that is sparking a rush. 
 
 Cobalt mining has not happened at any sort of scale in the United States for decades. 
 
 But a handful of mining companies are now staking claims at sites in Idaho, Montana and Alaska in search of the silvery blue mineral. 
 
 They are striking examples of the growing interest in cobalt - a key component in the lithium-ion batteries that power electronic devices and electric cars. 
 
 In the past, cobalt supply depended on the markets for copper and nickel, more valuable metals that are typically extracted alongside cobalt. 
 
 But with cobalt prices on the up and consumption projected to rise by between 8% to 10% a year, its status as a by-product has started to change, says George Heppel, senior analyst at research firm CRU Group in London. 
 
 Image copyright First Cobalt Image caption First Cobalt hopes to develop its Idaho mine in three years 
 
 About 300 companies worldwide are now on the hunt for cobalt deposits, CRU estimates. 
 
 Mining giants such as Glencore are also boosting production in the Democratic Republic of Congo (DRC), where most of the world's cobalt is found. 
 
 In the US, limited cobalt production started in 2014 for the first time in about four decades. 
 
 Canada-based First Cobalt bought a mine in Idaho this spring and hopes to get it developed in about three years. 
 
 Cobalt, rather than copper or another metal, is its main focus for the mine, says chief executive Trent Mell. 
 
 "Miners like us have never actually gone looking for cobalt," he says. "There's a lot of cobalt in the world. As miners, we're behind." 
 
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 Cobalt consumption is expected to exceed 122,000 tonnes this year, up from about 75,000 tonnes in 2011, according to CRU. 
 
 The price per pound (the measure used for cobalt) has risen above $40 this year, compared with about $20 in early 2011, and is now at about $32. 
 
 Although increased production is likely to help meet demand in the next few years, analysts say shortages loom by as soon as 2022. 
 
 Image copyright Getty Images Image caption A woman separates cobalt from mud and rocks near a mine in the Democratic Republic of Congo 
 
 The market dynamics have helped to build confidence, says Fiona Grant Leydier of eCobalt, which has revived plans for its own cobalt mine in Idaho that were first mooted in the 1990s. 
 
 The firm, previously called Formation Metals, now expects production to start towards the end of next year. 
 
 "The fundamentals for the cobalt market are so strong in a way that they have never been before," says Ms Grant Leydier. "We have a lot of interest from financiers, from potential partners and from potential employees." 
 
 After ore containing cobalt is mined using explosives, it is taken to be refined and turned into metal, blends or chemical concentrates for use in products such as jet engines, drones and batteries. 
 
 More than 60% of the world's cobalt is mined in the DRC, while China is the world's leading producer of refined cobalt. 
 
 But as demand for cobalt has risen, so have concerns in the US about its reliance on imports. 
 
 In February, the US added cobalt to a list of 35 minerals deemed critical to the economy. 
 
 Companies active in the US say they hope their "made in America" status will help speed up government approval for their plans and set their product apart from imports. 
 
 Image copyright Getty Images Image caption A conveyor belt carries chunks of raw cobalt after initial processing at a plant in Lubumbashi, DRC 
 
 They say concerns about corruption and child labour at mines in the DRC have also created pressure for buyers to find new sources of supply. 
 
 "There's a few places where you can get ethically mined cobalt and we want to be one of them," says Michael Hollomon, chief executive of Missouri Cobalt. "We would like to think that that gives us an advantage." 
 
 The company plans to start producing cobalt from an old lead mine in Madison County, Missouri this summer. It has an estimated 35 million pounds of recoverable cobalt, making it the largest such reserve in North America. 
 
 Nevertheless, the realities of where large, high-quality cobalt deposits are found globally mean the US will never be able to completely stop importing cobalt. 
 
 In fact, analysts expect the DRC's share of global production to increase as mining firms boost their activity there. 
 
 China is also expected to remain the world's dominant player for refining cobalt, even as new facilities start operating in Europe, North America and elsewhere in Asia. 
 
 Image copyright Ecobalt Image caption eCobalt has been planning a cobalt mine in Idaho for decades 
 
 Even though US companies remain a tiny fraction of the market, they may find they are able to command a premium price for their materials, says Caspar Rawles, an analyst at Benchmark Mineral Intelligence. 
 
 "Every company in the supply chain is looking to reduce their geopolitical risk, so I think any project outside of the DRC is in a strong position in that sense," he says. 
 
 The challenges remain significant, with the cost of setting up a mine running to hundreds of millions of dollars. The volatile price of cobalt presents another uncertainty. 
 
 Meanwhile, the rising cost of cobalt is pushing companies to find ways to reduce reliance on the mineral. 
 
 Gerbrand Ceder at the University of California, Berkeley is conducting research into ways of creating stable batteries that do not need large amounts of cobalt. 
 
 However, he says deploying such technology at scale - especially in cars - is at least five to 10 years away. "I think there will be quite a lot of cobalt used for some time to come." ||||| In an effort to avert potential production problems of its devices, Apple is in talks to directly acquire a critical mineral used in lithium-ion batteries. 
 
 The tech giant is negotiating with miners to buy thousands of metric tons of cobalt annually for a period of five years or more, Bloomberg is reporting, citing people who claim to have knowledge of the discussions. It’s still possible, however, that Apple’s discussions will fall apart. 
 
 Cobalt is a critical ingredient in lithium-ion batteries that power Apple’s iPhones, iPads, Apple Watch, and MacBooks. However, with cobalt demand soaring and supply constrained, a shortage of cobalt would be a major risk to Apple’s business. 
 
 By acquiring cobalt directly, Apple could ensure its battery manufacturing partners have the components they need to continue feeding batteries to the company. Apple might also be able to negotiate better cobalt prices because it would buy a larger quantity than smaller individual manufacturers that don’t purchase as much supply. The move could ultimately increase Apple’s margins on the sale of each device. 
 
 Still, cobalt is one of the most controversial materials in electronics. Two-thirds of the world’s cobalt supply comes from the Democratic Republic of Congo, where international human rights advocates like Amnesty International have said child labor is a problem. Apple and other prominent tech companies, including Samsung, have worked to ensure their cobalt supplies come from mines that don’t employ children. Buying supplies directly from miners would give Apple more visibility into labor practices on the ground. 
 
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 Nearly a year ago, Apple announced that it would stop buying cobalt mined by hand in the Congo until it could confirm companies in its supply chain had eliminated child labor and dangerous working conditions. 
 
 Apple did not immediately respond to a Fortune request for comment on the report.
– For the last four decades, cobalt mining has been almost non-existent in the US. That's changing now with what the BBC labels a rush for the precious metal recently named as critical to the US economy. With increases in price and demand for the silver-blue mineral—used in everything from the lithium-ion batteries to jet engines to drones—mining firms that have "never actually gone looking for cobalt" are doing so, says Trent Mell, CEO of Canada-based First Cobalt. His is one of several firms planning to dig for cobalt in the US, including in Idaho and Missouri, over the next several years. Along with the risks—there's availability and price volatility to consider, not to mention the hundreds of millions of dollars needed to establish a mine—comes the potential for big rewards. Consumption of cobalt—selling for $32 a pound, up from $20 in early 2011—is on pace to rise 8% to 10% a year, per the BBC. Indeed, some analysts expect to see shortages as soon as 2022. American-mined cobalt could ease the burden and might even fetch a premium price as the US looks to ease its reliance on imports and more companies begin to request ethical sources of the metal. ABC Australia reports that more than 60% of the world's supply comes from the Democratic Republic of Congo, where Amnesty International claims child slaves toil in mines. Some, however, see the rush as coming too late. Tiberius Group CEO Christoph Eibl tells Bloomberg that "the craziness that you see in cobalt will in many ways actually be corrected." For example, future batteries may use less lithium, he says. "There’s so much uncertainty about how future technologies will be applied."