Futures & Commodities

The bean rules gold

Gold vs. coffee

Thanks to coffee, Herb Greenberg owes me dinner.

One year ago my former colleague and current The Street.com columnist Herb and I made a bet over which would be the better one year investment: coffee or the gold miners.

Specifically, the wager was which ETF would perform better over the course of a full year. Herb locked in the Market Vectors Gold Miners ETF (GDX) and I picked the iPath Coffee ETF (CAFE).

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Though the investments were different, our rationale was similar: both investments had been wiped out, and we felt each may be near a bottom.

No investment is a no-brainer (if someone tells you it is .. RUN) but to me coffee wasn't too far off. Coffee drinking (demand) is up, while coffee crops (supply) had been hammered thanks to drought in Brazil and the dreaded Coffee Leaf Rust. Herb can lay out his own reasons for loving the miners.

In the end, both did well but my commodity of choice outperformed. The CAFE ETF posted a 19-percent return over 12 months, while Herb's GDX ran up just under 8 percent and includes a 0.72-percent dividend yield.

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Mercifully, the bet came to a close when it did. Recent coffee-price trends may have turned the tables on the bet. Brazil's coffee crop is coming back and prices are coming down (though with the heat and continued lack of rain again, 2015 may be another bullish year for the bean). Earlier in the year would've been a spectacular time to sell, as prices grew like a weed. Of course, the bet was for a full year so we were locked in.

As with my 2013 Japan prediction, keep in mind these predictions and fun dinner bets with my colleagues do not involve real money. Neither I nor my family invest in anything other than our company 401(k) plans.

But if you met Herb, you'd know dinner is a prize. A great guy with many good ideas and a plateful of market passion on the side. Herb, I promise to keep the dinner bill low(ish). Ready to make another wager?

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—Commentary by CNBC's Brian Sullivan. Follow him on Twitter @SullyCNBC