Diversified digger Anglo American (LSE: AAL) has managed to defy growing concerns over the health of the iron ore market in what has proven to be an eventful quarter. Indeed, the stock has gained 19% in value since the close of June.

A modest improvement in Chinese economic data has raised fears that monetary stimulus from Beijing could be about to hit the skids. This is adding to existing jitters over the abundance of stockpiled material in the country’s ports, not to mention fears over ongoing cutbacks to China’s steel capacity.

Against this backcloth, Anglo American is wisely continuing its policy of asset shedding across key commodities. Just last month the FTSE 100 (INDEXFTSE: UKX) giant sold its 70% holding in the Foxleigh metallurgical coal mine in Queensland, Australia.

But such measures are unlikely to be enough to turn the bottom line around as commodity prices look likely to keep struggling — Anglo American has endured heavy earnings drops in each of the past four years.

Besides, its proposed move out of heavily-oversupplied bulk commodities like iron ore and coal is coming under intense scrutiny. This month the Public Investment Corporation, the company’s largest stakeholder, suggested to Bloomberg that the divestment scheme should be put to a shareholder vote.

I believe a forward P/E rating of 16.7 times fails to fully reflect Anglo American’s poor sales outlook, in the near term and beyond and believe the strong possibility of further bad news in the weeks and months ahead could send the share price sinking.

Banking bothers

Financial leviathan HSBC (LSE: HSBA) has also flipped higher in recent weeks, ‘The World’s Local Bank’ rising 24% in value since the quarter kicked off. But I’m not so sure that the firm can keep this impressive run going.

I believe HSBC’s emerging market bias should pave the way for sterling returns in the long term, with rising population levels and rising affluence likely to power demand for financial products.

However, current economic turmoil in these regions looks likely to keep playing havoc with revenues at HSBC in the meantime. The company saw sales in Asia tank by almost a quarter during January-June, to $7.2bn. And an environment of low interest rates across the globe is likely to keep the top line under pressure.

But toiling sales aren’t HSBC’s only worry. The company still has a litany of misconduct-related issues to deal with across the world, and just last week was hit with a HK$2.5m fine by Hong Kong regulators for trading compliance issues on futures and options contracts. The size of the penalty can hardly be described as a game-changer, but is the latest in a steady stream of bad practices at the bank.

HSBC deals on a prospective P/E rating of just 13.2 times, below the FTSE 100 average of 15 times and suggesting that the bank’s shares are still undervalued. I disagree, however, and believe the bank could experience further significant pressure before things start to improve.

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