NEW YORK ( TheStreet) -- Western Refining ( WNR) and Potash ( POT) go ex-dividend Tuesday, meaning an investor must purchase the stocks Friday to qualify for the next dividend payment (markets are closed Monday for Martin Luther King Jr.'s birthday).

Both stocks get a buy rating from TheStreet Ratings.

Western Refining

Western Refining is an oil refiner. Western Refining divested its Yorktown, Va., facilities and an underused part of its crude oil pipeline in southeast New Mexico for $220 million to Plains Marketing and Plains Pipeline in December.

Forward Annual Dividend Yield:1.1%

Rated "B- (Buy)" by TheStreet Ratings: The company's third-quarter gross profit margin rose significantly from the previous year.

Western Refining has average liquidity. Its Quick Ratio is 1.22, which demonstrates that the company can technically meet its short-term cash needs.

In the third quarter, stockholders' net worth increased 29.79% from the previous year.

TheStreet Ratings' price target is $18.99. Shares of Western Refining closed Thursday at $15.13.

Potash

Potash is a fertilizer company that is involved in feed and industrial products. The company is scheduled to release its fourth quarter and full-year 2011 earnings on Jan. 26. The average analyst estimate for earnings per share is 90 cents on $2.14 billion in revenue, according to Thomson Reuters.

Forward Annual Dividend Yield: 0.7%

Rated "B (Buy)" by TheStreet Ratings: The company's third-quarter gross profit margin rose significantly from one year ago.

Potash's liquidity is weak. Its Quick Ratio is 0.79, which demonstrates a lack of ability to cover short-term cash needs.

In the third quarter, stockholders' net worth decreased 4.88% compared to the previous year.

TheStreet Ratings' price target for Potash is $49.71. Shares of Potash closed at $43.45 on Thursday.

-- Written by Alexandra Zendrian

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