Should you buy last week’s winners Antofagasta plc, Supergroup plc and International Consolidated Airlns Grp SA?

Copper play Antofagasta (LSE: ANTO) continues to benefit from ‘rush to safety’ share investing, the business gaining 11% in value between last Monday and Friday. The South American producer has benefitted from red metal values vaulting back above the psychologically-crucial $5,000 per tonne marker in recent days.

I find this somewhat surprising however, given that economic data from commodities glutton China continues to disappoint. Indeed, latest trade numbers showed copper imports slip 2.3% month-on-month in June, to 420,000 tonnes.

And stocks data from the London Metal Exchange rubber-stamps the patchy state of underlying copper demand — total inventories currently stand around 230,000 tonnes, up around 20% from the start of the month.

These worrying fundamentals leave copper values in danger of a severe retracement, in my opinion, and with it the share value of Antofagasta. And I reckon the mining giant’s huge forward P/E rating of 60.2 times certainly increases the likelihood of a rapid dash to the exits.

Retailer roars

I’m far more optimistic over the investment prospects of fashion play Supergroup (LSE: SGP), however. The stock gained 16% in value last week as latest financials revealed further breakneck revenues growth. Supergroup saw sales detonate 21.3% during the 12 months to April 2016, to £590.1m, a result that drove pre-tax profit 16.3% higher to £73.5m.

The Superdry designer’s huge investment in developing its e-commerce proposition is clearly paying off handsomely, as is the introduction of new ranges like its Superdry Sports and Idris Elba-monikered products.

Supergroup is the tonic for those fearful of deteriorating retail conditions in its home market, in my opinion, and I reckon this factor could keep shoving the share price higher. Supergroup is steadily expanding across Europe, while its entry into China and beefed-up US presence also promise hot sales potential.

As such, I reckon a P/E rating of 19.8 times for fiscal 2017 is very decent value.

Flying higher

Global travel giant International Consolidated Airlines (LSE: IAG) also recovered some ground between last Monday to Friday, a 13% week-on-week advance making it the FTSE 100’s best riser.

Still, I reckon IAG has plenty in the tank to keep rising. The company still deals at a 20% discount to pre-referendum levels, and currently changes on a ridiculously-cheap forward P/E rating of 5.3 times.

IAG isn’t without risk, of course, as Brexit Britain forces people to put the kibosh on big ticket purchases like holidays. Indeed, the flyer advised that “while [we] expect a significant increase in operating profit this year,” this rise isn’t expected to match the explosive growth witnessed in 2015.

However, IAG commented that the EU withdrawal “will not have a long-term material impact on its business.” And I can understand why — IAG is at the forefront of transatlantic travel, while it’s also increasing its presence in the fast-growing budget market.

Last week the firm advised it was converting options for two Airbus 330-300 craft into firm orders for its Aer Lingus brand, a move that should give investor confidence a huge shot in the arm.

I believe the troubles facing IAG are more than baked into the price at current levels.

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