Rare Earth Minerals (LSE: REM) and Sirius Minerals (LSE: SXX) have been two of Motley Fool’s most actively followed stocks lately, both boasting an avid — if nervy — fan base.

The fans have had reason to cheer, however, as both have enjoyed some good news in recent months. In August, Rare Earth Minerals announced a tie-up with electric sports car and energy storage company Tesla Motors that did wonders for its prospects and profile.

Deep Resources

Sirius Minerals has been edging closer to full approval for its potash project beneath the North York Moors, where it hopes to dig the planet’s largest polyhalite mine to fertilise the world’s farms. Neither company has dug up any money, but they have massive potential. The “will they, won’t they” nature of both stocks has captured investors’ attentions but ensured volatile share price performance.

Sirius is up 73% over the last six months to 18.25p, as it awaits the planning green light for its polyhalite plans. Over the same period, Rare Earth Minerals is down around 20% to 0.98p, albeit with plenty of highs and lows in between. Both companies have a long journey before they actually generate any revenues, but markets clearly seem to that Sirius now has the smoother road.

Battle Of York

We should know for sure quite soon, as news emerges that the North York Moors National Park Authority will circulate its final decision notice and other relevant documentation for signatures this week. The verdict should be issued shortly afterwards: investors will be crossing their fingers and toes.

If it gets the answer it wants, chief executive Chris Fraser still has to raise up to £2bn to develop the potash mine and Teeside export links. Management has struck a series of morale-boosting polyhalite supply agreements with major agri-business customers, but none will bear any fruit until the mining starts, and that is some way off.

The Bacanora Story

Investors in REM also face an anxious wait. Tesla has high standards and has set tough “performance milestones” for the lithium hydroxide it needs to manufacture batteries at its $5bn Gigafactory in Nevada. It could be two years before we know for sure whether it has met those milestones. That said, Tesla has a strong interest in the success of REM and its partner Bacanora Minerals, and won’t want to see the project fail. If it succeeds, REM has the tasty carrot of a five-year contract, with a potential five-year extension to follow.

Both stocks have been relatively quiet in recent weeks as investors await the next development. Many traders have quit the scene, as the prospect of a short-term gain recedes. Even if Sirius gets the final decision it wants, as markets appear to assume, it still won’t make any money for several years. Rare Earth Minerals faces a similar challenge.

Both of these stocks could prove big winners for your portfolio, but investors will have to dig deep into their reserves of patience to find out, without a single dividend as a reward.

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