It’s not often that a share price more than seven-bags in just 16 days, but that’s what’s happened to 88 Energy Limited (LSE: 88E), whose shares have soared from just 0.34p to 2.3p since 9 February and have lifted the company’s market cap from just a few million to £26m! So what’s happened?

It’s all down to a major shale discovery in the firm’s Icewine Alsakan exploration announced on 15 February, after anticipation had already been pushing up the price. But the big question is, can the shares in this AIM tiddler keep on going?

Well, the discovery looks like it could be very high quality stuff, with the initial announcement telling us the asset lies in a “thermal maturity sweetspot” (which is, apparently, a very good thing indeed). Then a further update on 29 February made the shale deposits sound even better than originally thought.

Although the apparent quality of the discovery means a profitable farmout deal might be possible, the big risk is that 88 Energy actually has no revenue and there’s no idea yet of the costs to turn Icewine into a productive asset or of where the cash might come from. Still, if you’re brave enough for the risk, you might want to take a closer look.

Minerals recovery?

Shares in Amur Minerals Corporation (LSE: AMC) have lost 83% since their peak in June 2015, to 6.62p, but since a low on 16 February they’ve actually picked up 31%. News of the company’s intended 2016 developments at its Kun-Manie nickel copper sulphide project in far eastern Russia seem to have pleased investors, as the company has been investing in new equipment that has doubled its drill capacity. The new kit is due to be sent out over the ice road this month.

Amur should be able to drill to a depth of 15,000 metres this year, it says, and the company is teetering on the edge of profitability. This year could even be the year in which Amur turns its back on a few very slow years. And I do think that, with production costs being low and its cash reserves strong after December’s equity issue, there’s a decent long-term future for the company. But it’s not without risks, not the least of which is that it’s under Russian political control.

Renewable profits?

AFC Energy (LSE: AFC) is another that I think could be set to turn the corner towards profit, despite its shares having lost 71% of their value since July 2015, to 16.7p.

What encourages me about the fuel cell developer is its strategic milestone plan for 2016, just released on 1 March. It includes developing a second-generation fuel cell plant, and giving it an extended test of more than a month while confirming it meets industrial standards. It also includes finalising design and engineering of its 10kW and 1MW systems, and enabling deployment in 2016 and 2017, respectively; and progressing with a number of international fuel cell projects and strategic partnerships.

I see a promising long-term future, so why are the punters apparently unimpressed? I suspect the main reason is the probably the long lead time before AFC can expect any profits, coupled with very few analysts covering the stock and an absence of recommendations. One for the bold I think.

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Alan Oscroft has no position in any shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.