It's no surprise that international stocks have gained popularity with investors over the past few years. They've generated absolutely amazing growth.

For the sixth year in a row, the Vanguard Total International Stock Market Index outpaced the Vanguard Total Stock Market Index. The latter tracks the broad U.S. market, including top holdings in PepsiCo (NYSE: PEP) and Merck (NYSE: MRK).

Even though foreign markets probably won't outperform U.S. markets every year, international stocks are undeniably worth your time to research. And thanks to American Depositary Receipts (ADRs), U.S. investors have more opportunities than ever to trade foreign securities on domestic exchanges.

This month's best performances
Foreign companies that participate in an ADR program must file reports in accordance with U.S. regulations and accounting standards, but their different corporate cultures and business decisions can seem unorthodox to American investors.

To help us understand this month's top-performing ADRs, we'll tap the expertise of more than 89,000 investors participating in Motley Fool CAPS, the Fool's free investing community. Here are the past month's top-performing ADRs, along with their ratings from the CAPS community.

Company

% Change

CAPS Rating
(out of 5)

Harmony Gold Mining (NYSE: HMY)

37.1%

****

Chemical & Mining Co. of Chile (NYSE: SQM)

31.9%

*****

Tenaris SA (NYSE: TS)

29.4%

*****

Tele Norte Celular Participacoes

27.9%

NR

Madeco SA (NYSE: MAD)

26.7%

****

Data provided by Capital IQ, a division of Standard & Poor's, and Motley Fool CAPS as of Mar. 18; screen excludes companies with market cap below $100 million. NR = not rated.

Remember, I chose these stocks as jumping-off points for further research, not formal recommendations. That said, the CAPS four- and five-star ratings for stocks such as these are an effective tool for investors.

We told you so!
Last month, CAPS investors picked Chemical & Mining Co. of Chile (a.k.a. "Sociedad Quimica y Minera" or "Soquimich," depending on your circle) as the best South American stock in CAPS-land. In fact, it's been rated a five-star stock for more than six months.

Before we jump into what CAPS investors are saying about Soquimich, here's a little company background. It is a leading global exporter of fertilizer, specifically potassium nitrate, which is used to improve agricultural yields. With wheat and other foodstuff prices soaring, you can bet that farmers are knocking on Soquimich's door for more products.

The company is majority-controlled by three investors: Chile's Julio Ponce, Norway's Yara International ASA, and Potash Corp of Saskatchewan (NYSE: POT). (The latter two are also in the fertilizer business.)

But Soquimich isn't just a one-trick pony. It also produces iodine, which has a wide variety of uses, from antiseptic to x-ray media. Moreover, Soquimich is the world's largest producer of lithium, and lithium demand is on the rise for laptop batteries and hybrid vehicles.

A CAPS pitch from cfsguy99 speaks to Soquimich's geographic advantage in the lithium industry:

This major producer of Lithium-Ion materials for the world Lithium market can be expected to continue to grow as demand for electric car batteries increases. Lithium is the current 'next generation' battery technology... [W]ith the release of several L-Ion battery based cars coming out in 2008, now would be a good time to invest in producers of industry materials. Check google-earth in northern Chile to see the pools (of lithium).

Income-minded investors will also be pleased to see that the stock currently boasts a 2% dividend yield. According to Soquimich's most recent report 20-F, the company's board of directors has traditionally used "a policy of paying a single dividend ranging from 50% to 65% of our consolidated net income for the year," even though Chilean law only requires the company to distribute 30%. This year, the proposed distribution will be $4.4459 per ADR. The record date for ADR holders has yet to be announced.

In this Fool's opinion, you should listen to CAPS investors on this one. Soquimich certainly has some intriguing qualities, and it appears well-positioned to capitalize on the growing need for fertilizer products, iodine, and lithium power. The stock's fate is obviously tied to the demand for these products, however, so be sure to research those submarkets further before making any investment.

What do you think about Soquimich, or any stock for that matter? Make your voice heard on Motley Fool CAPS. It's 100% free, so sign up today!

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Fool contributor Todd Wenning puts his shoes on one at a time, just like everyone else. He does not own shares of any company mentioned. The Fool has a disclosure policy.