You don't need a reminder that the Chinese stock market took a dive this week. That, combined with a few untimely comments from bearish economists, sub-prime lenders facing 'issues', housing foreclosures up, housing starts down, oil prices up and squabbling in Washington about federal spending took its toll and rattled world markets.

This writer remains an optimist -- and a pragmatist, which is of at least equal importance -- and still the contrarian. I don't care how scary China looks right now to some, this is a buying opportunity. Here's how I see it: In the long run the market is going up! The Chinese market will be the biggest market! And I want to buy at bargain prices for the long term!

The Aluminum Corporation of China ADS (NYSE: ACH), which I have discussed before, has not been mentioned in the conversations about Alcoa Inc (NYSE: AA) possibly being a buy-out candidate, or in the comparisons with Alcan Inc. (NYSE:AL), its Canadian competitor.

ACH closed yesterday at $22.98, with a P/E under 8.0 and a 5.5% dividend yield. In addition to this, the P/S was 0.65, and the P/B was 0.62. To me this indicates a tremendous value. What if its profits were to drop in half? Well, surprisingly, it would than be about par with Alcoa.

For comparison, Alcoa has P/E of 14.0 and a 2% dividend yield. The P/S was 1.17, and the P/B was 2.07. These are very favorable numbers, and I actually considered Alcoa to feature here. But, as you can see, it seems far more pricey than ACH. Also considering that Alcoa has been mentioned as a buyout target at a considerable premium to its current valuation - that only makes ACH look even cheaper. ACH has only been public for about 5 years, chart below.

You can see that it has had a wild ride but clearly an upward trend.