Startups are notorious for solving difficult problems.

Others see speedbumps as hindrances, but early-stage companies view them as the opportunities that could catapult them to riches.

Generally speaking, mankind’s optimism for addressing substantial problems like climate change is, whether it knows it or not, in large part attributable to the ingenuity and audaciousness of startups.

While many say “we can’t,” startups take a more glass-half-full approach of asking “why can’t we?”

And while moonshot technologies might be difficult for established corporations to conceive, develop, and eventually adopt, smaller companies know this risk-reward proposition is the name of the game.

In fact, there is one such technology on the verge of mass adoption that’s unlocking previously untapped reserves of one of our most widely-used natural resources: copper.

Practically every piece of technology you own requires copper wiring. It’s the biggest reason why copper is the world’s third-most-used metal.

So, there is understandable concern surrounding the global copper supply which, in the face of breakneck demand, was projected to produce a more than 4.4-million-ton supply-demand deficit by 2030.

Thanks to startups, though, that past tense “was” is officially a point of emphasis.

The last technological innovation in the copper industry came all the way back in the 1980s. Since then, extraction of copper has been restricted to two methods – crushing, concentrating, and refining sulfide ore, and using electro-chemical processes to extract copper from oxide ore.

However, there was a lot of copper being left on the table – copper that traditional sulfide ore extraction would have proven too expensive to undertake and oxide ore extraction ineffective.

Thanks to the work done by Jetti Resources, a U.S.-based startup, to develop its technology (in conjunction with the University of British Columbia), that untapped copper is now very much in play.

As a result, what was previously viewed as “waste material” is quickly transitioning to viable.

“The industry has accumulated this waste material forever,” Jetti founder and CEO Mike Outwin told Fortune. “They’ve been trying to come up with an answer for it on their own for a couple of decades and haven’t been able to.”

All of that helps explain how Jetti recently secured $100 million in its Series D at a $2.5-billion valuation, further evidence that worthy startups have no issue securing capital despite the current landscape.

That said, it’s a useful reminder of the value established technologies bring to the table in terms of raising capital.

“Jetti is very real. It’s not lab tests or pilot plants. Jetti has been deployed commercially,” said Outwin. “Our partners will make extraordinary profits from being able to utilize our process, and Jetti will do well.”

In a classic example of the problem-solution relationship of startups, Jetti appears well on its way to becoming a fixture in its given field.

When it comes to assessing angel investment opportunities, it’s always important to identify the biggest problems.

You can rest assured there are startups working feverishly to solve them.