It’s not an overstatement to say that mining stocks have been taking it on the chin…

Precious metals have been famously beaten up since 2011, and the gold and silver miners have gotten it worse than the metals themselves.

Industrial use metals have been participating in the carnage, as well. But, as we know, carnage sometimes presents opportunity.

Copper, for instance. has recently seen its reserves climb and its prices fall. Along with weakening economics in high demand areas like emerging markets, the bottom lines of many copper miners and producers have been hurt.

One copper company, in particular – Southern Copper Corporation (SCCO ) – is down 40% year-to-date. But with a current dividend yield of more than 12%, it might look attractive to some investors, nonetheless.

Of course, looks can be deceiving…

Copper in the Crapper

“How low can it go?” is a commonly asked question when an investment drops precipitously.

Lower prices can lure investors into seeing bargains where there are none. And, in this case, the fact that the price of copper is going lower is creating the appearance of opportunity.

“Appearance,” because even though no one doubts that copper will continue to be in demand in the future, demand is only half of the equation.

The other half, of course, is supply. And how much (or how little) of it will determine whether the price goes back up or heads further down.

You see, the iPath Dow Jones UBS Copper Total Return Sub-Index ETN (JJC ), which tracks the copper index and is invested in copper futures – and not copper stocks – is down more than 21% year-to-date.

That’s bad enough, but still not as bad as the spot price of copper, down nearly 27% since January.

Worse is the Global X Copper Miners ETF (COPX ), which invests in copper mining companies. It’s down even further – almost 40%. That’s more than enough to make its otherwise decent dividend yield of 5% irrelevant.

Copper Glut Now, Dividend Dearth Later

If you crack open the holdings within the Global X Copper Miners ETF, you’ll find that the third-largest position is Southern Copper.

That’s hardly a surprise, considering that the company is one of the largest copper producers in the world.

But the company’s size can’t save it from the fact that, like other mining stocks, it’s been negatively affected by the glut of copper in world markets, weakening demand.

So while the price of the stock has come way down, and may look like a bargain, there’s reason to doubt the future recovery of the stock price.

Morningstar analysis determines the price at about fair value, but states that the company will be directing more money in the future to investments and, accordingly, away from dividend distributions.

That’s a worrisome prospect, because the dividend is a very attractive aspect of the stock. Possibly the only attractive aspect.

At 12%, the yield checks in very high by today’s standards. But, as always, underlying the extreme yield is unreliability.

Case in point: While the company has indeed been paying a dividend every year since the mid-nineties, the amount of the dividend has varied over the years.

Since 2009, the distribution has been growing – but along with it, so has the dividend payout ratio. And its current level of 176% is well beyond the bounds of sustainability.

Translation? Either earnings rise mightily (least likely) or dividends get cut (most likely).

Bottom line: Between copper’s uncertain future and Southern Copper Corporation’s wavering, unsustainable dividend, income investors can undoubtedly achieve safer, more reliable yields elsewhere.