Sirius Minerals plc isn't the only stock with a promising future

Thanks to the huge volatility often experienced in the commodities markets, mining stocks aren't for the faint-hearted. Nevertheless, those willing to take on more capital risk with their investments could see dramatic improvements to their wealth, so long as the companies they choose to buy continue to provide evidence that they are gradually bringing their projects to fruition.

Thursday's announcement that SiriusMinerals(LSE: SXX) had signed a 'take or pay' offtake agreement for the sale of its POLY4 product to one of the leading agribusinesses in South East Asia is a perfect example of the this.

Once delivered, PT Chemical Indonesia -- a subsidiary of Wilmar Group -- will sell the polyhalite into territories such as Indonesia, Malaysia, Thailand and Vietnam, as well as using it within its own farming operations.

Clearly, having such a massive company as a customer won't do Sirius's profile any harm at all. The fact that the FTSE 250 miner will now be supplying "one of the fastest growing fertilizer regions in the world" should bring it to the attention of more potential buyers who may be tempted to agree on something similar to the seven-year deal (with the option of a further three years) made with Wilmar.

Having moved sideways for the last few weeks, I'm beginning to think it won't be long before Sirius's shares spring to life and get closer to the 60p price target agreed by numerous analysts. True, production is still a long way off but recent construction updates from the company suggest that everything appears to be on schedule and on budget -- no small feat for a mining company.

Still a risky bet? Of course. As a stock to tuck away and forget, however, I think Sirius takes some beating.

High grade deposit

Investors looking for more exposure to the mining sector -- but sensible enough to diversify their holdings -- may wish to take a closer look at £47m-cap Horizonte Minerals(LSE: HZM).

It might be a market minnow, but Horizonte owns 100% of one of the largest and highest grade undeveloped nickel saprolite resources in the world - in the form of its Araguaia project in northern Brazil. When you consider just how much of the metal is likely to be required as electronic vehicles become increasingly common (not to mention the growing use of renewable fuel technologies such as wind turbines), that's quite an asset to have in your possession.

Last week, the company submitted its application for a mine construction licence to SEMAS (the Par State authority responsible for environmental licencing) -- "a major milestone", according to CEO Jeremy Martin.

With a fully-funded feasibility study of the Araguaia project now due for completion in Q1 next year, it wouldn't be surprising if Horizonte began to hit more investors' radars, particularly given the hugely attractive economics of the project. Once in production, it has been suggested the company could be one of the lowest cost producers around, generating $1.3bn in free cash flow over the mine's 28-year life, based on a nickel price of $12,000 per tonne.

A further positive to Horizonte is the strong institutional backing the company has. With investors including Glencore and JP Morgan, you can be fairly certain that raising finance to construct the mine won't be an insurmountable obstacle.

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Paul Summers owns shares in Sirius Minerals. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

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