Those fearing the fallout of Brexit on their share portfolios have been piling into the commodities sector left, right and centre.

The UK isn’t a prolific importer of raw materials, after all, so at face value this appears to be a wise manoeuvre. Indeed, this line of thinking has thrust copper stock Antofagasta (LSE: ANTO) 5% higher since the polls closed.

Having said that, Britain’s withdrawal could have a devastating impact on the global economic landscape for some time to come, with many commentators touting a hefty decline in global trade. As such, commodities demand from China could come under pressure should the country’s exports take a tumble.

Metals markets are already being hampered by poor supply/demand outlooks as the next generation of ‘mega projects’ steadily come online. Indeed, Bank of America expects copper to average $4,625 per tonne in 2017, down from 2016’s tipped average of $4,828.

Given these risks, I reckon Antofagasta is far too expensive given its huge forward P/E rating of 62.1 times, and reckon a correction could be just around the corner.

Gold goliath

However, my bearish take on the commodities sector doesn’t mean all of the Footsie’s diggers are destined for prolonged share price weakness.

Indeed, I’m becoming increasingly positive over the outlook for gold play Randgold Resources (LSE: RRS) and its precious metals peers. And so is the wider market — the stock has seen its share price advance 45% since last month’s referendum.

Gold prices have marched higher as concern over the impact of Brexit on the global economy have hit fever pitch. And these fears are unlikely to disappear any time soon as the UK’s withdrawal from the EU is likely to take several years.

On top of this, expectations of a Federal Reserve rate hike in the months ahead have also been thrown onto the bonfire, and with it predictions of a resurgent US dollar. This has provided dollar-denominated gold with an extra support lever.

Sure, Randgold’s elevated P/E multiple of 41.7 times for 2016 may appear heady on paper. But I believe the scale of investor jitters leaves room for the stock to punch extra gains.

Powering up

Like Randgold, I reckon National Grid (LSE: NG) could also continue to thrive in the current environment.

Of course the essential role of electricity in the modern world makes National Grid a great pick for those seeking terrific earnings visibility. And this is likely to become more and more important as the macroeconomic picture deteriorates.

But aside from this, National Grid could also see its share price accelerate as dividend chasers pile into the stock. The profits outlook for previously-big payers like banks, airlines and housebuilders is coming under increased scrutiny, and this could see the utilities segments become increasingly popular should the aforementioned sectors show signs of stress.

National Grid’s share price has jumped 12% since June’s referendum. But I believe a forward P/E rating of 17.6 times is still an attractive buying level in the current climate.

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Royston Wild 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.