The quest for gold has long spurred humankind's bold exploration of new frontiers. From the Age of Discovery, to the American westward migration that followed, the promise of untold treasures over the horizon has shaped our collective history in profound and lasting ways. It looks like the mining industry may be preparing to look skyward for the next frontier, but before we get into that, I want to briefly touch upon some of the bold moves under way right here on our home planet.

New frontiers here on planet Earth
Here, in the 21st century, we continue to open new frontiers in the quest for gold and silver. Newmont Mining (NYSE: NEM) ventured into the far north in Canada's Nunavut territory for the alluring Hope Bay project. But as with many bold adventures, the economics just wasn't there yet, and Newmont booked a $1.6 billion writedown during the fourth quarter of 2011. After a transformational journey into China, Eldorado Gold (NYSE: EGO) is trekking the silk road to develop attractive gold deposits in Greece.

Aquatic pioneer Nautilus Minerals moved another step closer this week to becoming the first commercial seafloor miner by signing an offtake agreement with China's largest importer of copper concentrates for the massive sulphides to be mined off the coast of Papua New Guinea.

Following decades of relative indifference, the 21st century has witnessed a rapid resurgence in the role of gold and silver as monetary metals. Accordingly, some former frontiers of gold and silver production that had grown quiet are springing to life once again. In the Yukon, Alexco Resource (AMEX: AXU) brought the legendary Keno Hill silver district back into production. Meanwhile, nearby explorer ATAC Resources has discovered the only known Carlin-style gold deposit outside of Nevada with the Rackla gold project.

And in Nevada, where pioneering investors today can stake their claim to a growing miner like Allied Nevada Gold (AMEX: ANV) near its 52-week low, McEwen Mining (NYSE: MUX) is opening new frontiers in gold exploration by using geochemical analysis of groundwater samples to help locate the mines of tomorrow.

Gold mining in the 22nd century
The interplanetary mining company depicted in the movie Avatar did not exactly offer a stellar image of hypothetical resource extraction in space, but that hasn't deterred director James Cameron from putting some skin in the game. Along with a line-up of deep-pocketed supporters that includes Google executives Larry Page and Eric Schmidt, Cameron is supporting a venture called Planetary Resources that intends to first explore, and then potentially mine for precious and rare-earth metals on nearby asteroids. Of course, rare-earth minerals would then require a new name.

With a boldness typical of fresh ventures into new frontiers, the project's proponents suggest that mining of near-Earth asteroids will "add trillions of dollars to the global GDP" and "help ensure humanity's prosperity." Something tells me that Treasury Secretary Tim Geithner and Federal Reserve Chairman Ben Bernanke must have breathed an asteroid-sized sigh of relief when they picked up their morning papers and saw the encouraging headline. Given the severe financial dilemma in which the world finds itself today, space rocks indeed may provide the most realistic source of payment of the massive debts incurred.

As a product of the Star Trek generation, I can't help but get excited by the thought that humankind may step out into space in a more material way during the course of my lifetime. I wish the venture well, and trust that the eventual execution will look nothing like the planet-destroying miner depicted in Avatar. At the same time, as a careful observer of our existing mining industry here on Earth, I can't help but focus my gaze upon the glaring irony here.

You see, despite a powerful bull market in gold and silver prices, the stocks of gold and silver miners continue to suffer from a noteworthy condition of underinvestment. Countless junior explorers right here on Earth can barely scrape together a few million dollars at a time to keep an exploration drill or two turning at their most prospective properties. Lured by paper gold and bullion proxies, investors have failed to engage the ongoing bull market through the mining equities as they did in past bull-market cycles. The severity of this underinvestment will be felt in time, as ultimately this will filter down to the supply picture and push metal prices higher.

While I am glad we have some forward-thinking billionaires who are willing to bankroll space exploration now that NASA can't afford it, I consider it the height of irony that those same billionaires seem to have no interest in mining ventures right here on Earth that are far closer to production and far more economically viable. Until such time as the mining and exploring equities here on Earth reflect a reasonable value for the buried treasure contained within their property portfolios, I would remind these billionaires that they may find themselves even better equipped to fund this long-term space venture if they were to also invest a bit of capital in mining just a little closer to home.

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