Copper was the darling of commodity traders. The price rallied from about $6,400 per ton to a record $10,190 in the past year, The Financial Times reports. Momentum was strong and it looked like there was no end in sight. But now, prices have dropped off a bit and miners are worried that the rally has hit a brick wall. The main concern is that what drove drove prices skyward -- China's demand -- may be slowing, according to the FT.

One indication of the slowdown is the amount of stocks held in exchange warehouses. At the LME Asia + Shanghai exchange warehouses, copper stocks have increased from below 150,000 to over 325,000 tons. That buildup has worried miners. The companies affected are Freeport MeMoRan (FCX), BHP Billiton (BHP), Xstrada (XSRAF), Anglo American and Brazil's Codelco, according to the Financial Times.

Founded in 1989, Chesapeake Energy (CHK) has grown to become the second largest producer of natural gas and one of the most active drillers of new wells in the U.S. Chesapeake competes with other oil and gas producers like Exxon Mobil (XOM), ConocoPhillips (COP), Anadarko (APC), BP (BP) and Chevron (CVX). Chesapeake owns interests in around 44,100 producing natural gas and oil wells that are currently producing around 2.4 billion cubic feet equivalent (bcfe), 93% of which is natural gas.

Alcoa (AA) is the world leader in the production and management of primary aluminum, fabricated aluminum and alumina. The company has a significant presence in all segments of the aluminum industry and operates in more than 31 countries worldwide. The company competes with other international metals and mining giants like Rusal, Rio Tinto (RTP), BHP Billiton (BHP) and Chalco (ACH).

The company recently released its Q4 2010 earnings, and we have updated our price estimate to $17.68 based on a reduction in total debt, an increase in revenues from better product pricing and better cash management leading to cost savings.

Primary Metals the Biggest Driver of Value

The primary metals division produces primary aluminum used by Alcoa's fabricating businesses, and it is sold to external customers, aluminum traders and on commodity markets. While our analysis shows that it was Alcoa's most valuable division in terms of contributor to shareholder's income, we have further increased our estimates for the overall value of the division going forward.

Aluminum prices have increased over the last two years since their sudden decline from peak prices in mid-2008. The 13% increase in global aluminum prices in 2010 has been directly responsible for the observed increase in the division's revenue.

We capture the impact of the aluminum prices on Alcoa's revenues in our forecast for the yearly average price of primary metals.

With demand for aluminum predicted to increase from 10-15% in developing countries like China, South Korea, Thailand and India, Alcoa's estimate of a 12% growth rate for 2011 is well justified. We believe that the demand growth will increase Alcoa's revenue per ton of aluminum sold to as high as $3,400 in coming years from its current value of about $2,500.

See the complete $17.68 Trefis Price estimate for Alcoa's stock.

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U.S. stock futures are mixed this morning, as investors are awaiting economic data on retail sales and manufacturing activity in the New York area. Futures on the Dow Jones Industrial Average rose 3 points to 12,227.00 and S&P 500 futures fell 0.30 point to 1,327.40. Nasdaq 100 futures gained 1 point to 2,382.75.

European markets were mixed today. While STOXX Europe 600 Index has gained 0.12%, London's FTSE 100 Index moved down 0.06%.

Asian markets ended mixed, with Japan's Nikkei Stock Average gaining 0.20% and Australia's S&P/ASX 200 moving down 0.08%.

Shares of Anadarko Petroleum (APC) gapped higher right out of the gate Thursday morning, thanks to a report that BHP Billiton (BHP) may be eyeing the firm as a potential takeover target. According to the U.K.'s Daily Mail, BHP could be prepping an offer worth $90 per share to acquire Anadarko. However, neither company has issued a formal response to the speculation.

After jumping to a new annual high of $76.50 bright and early Thursday morning, APC is on pace to notch a weekly finish atop the $70 level for the first time since April 23. In fact, if the shares can maintain their positive momentum through Friday's close, the shares could stage their first weekly victory north of $75 since June 2008.

"Commodities are experiencing a long-term bull market that will last for years, despite periodic ups and downs," notes Yiannis Mostrous, editor of The Silk Road Investor.

Mostrous -- author of the just-published The Rise of the State: Profitable Investing and Geopolitics in the 21st Century -- explains, "Our latest new buy is BHP Billiton (BHP) is the world's largest mining company by market capitalization.

Australian mining firm Rio Tinto (RIO) revealed plans to triple its capital expenditure to around $11 billion. The company also plans to up its iron ore production by more than 50% during the next five years.

The boost in production stems from new drilling and a reevaluation of deposits in Western Australia where the company found an extra two billion tons of iron ore reserves. The expansion of the iron ore division should help RIO take advantage of the "growing demand for raw materials to make steel" in China.

Analyst Upgrades

• Citigroup upgraded Mosaic (MOS) to buy from hold and raised its price target to $78 from $64 citing improving ag fundamentals and the potential for BHP (BHP) to issue a higher bid for Potash (POT), which Citi feels would bode well for Mosaic.
• Cowen upgraded VMware (VMW) to outperform from neutral, citing recent share weakness and the company's significant growth opportunity.
• Citigroup upgraded CareFusion (CFN) with a $29 price target, citing valuation and the potential for margin expansion.
• Pfizer (PFE) was upgraded to outperform from neutral at Cowen.
• Juniper (JNPR) was upgraded to outperform from perform at Oppenheimer.
• Stryker (SYK) was upgraded to buy from gradually accumulate at Soleil.

Reportedly, Potash (POT) is considering joining forces with global firms that would be able to present an offer to compete with BHP Billiton's (BHP) $38.6 billion bid.

According to The Wall Street Journal, people "familiar with the matter" stated that there could be a global consortium in the works to make a counteroffer for Potash. BHP has gone straight to Potash shareholders with its offer of $130 per share.

In the wake of the BHP Billiton's (BHP) failed $39 billion offer and its new hostile $40 billion takeover bid for Potash Corp. of Saskatchewan (POT), agricultural fertilizer companies, including CF Industries Holdings (CF), are starting to look pretty juicy to investors.

Fertilizer companies have been struggling during the past few years as cash-strapped farmers have been pulling back on their purchases, but the tide appears to be changing.

With rising prices for crops like wheat and corn, it is starting to look like it is going to be a really good year for U.S. farmers, which means they are going to have plenty of money to reinvest in new machinery and more fertilizer.