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Sector Losers: Worst Performing Stocks Over Last Week (Basic Materials) - (BPT, ZAZA, PBT, ANR, ACI)

|Includes:AKS, ARCH, AU, BP Prudhoe Bay Royalty Trust (BPT), GFI, HMY, KRO, NBR, PDS, SJT, UPLMQ, WLT, ZAZA

The following is a list of the worst performing Basic Materials stocks over the last week.

The list has been sorted by each stock's alpha vs. their industry average.

To help you explore the companies listed below, we've also included links to industry descriptions and corporate websites.

More Lists Like This: Worst Weekly Returns in Basic Materials Sector

All data current as of 8/29/2012.

1. BP Prudhoe Bay Royalty Trust (NYSE:BPT): Returned -28.29% over the last week vs. an industry average of 0.36%. (Industry: Oil & Gas Refining & Marketing. Alpha vs. industry at -28.65%, based on average of 27 companies)

Operates as a grantor trust in the United States.

2. ZaZa Energy Corporation (NASDAQ:ZAZA): Returned -14.17% over the last week vs. an industry average of -1.18%. (Industry: Oil & Gas Drilling & Exploration. Alpha vs. industry at -12.99%, based on average of 52 companies)

3. Permian Basin Royalty Trust (NYSE:PBT): Returned -13.69% over the last week vs. an industry average of -1.72%. (Industry: Independent Oil & Gas. Alpha vs. industry at -11.97%, based on average of 72 companies)

Permian Basin Royalty Trust owns overriding royalty rights in mineral properties in the United States. (Link to Permian Basin Royalty Trust website)

4. Alpha Natural Resources, Inc. (ANR): Returned -13.76% over the last week vs. an industry average of -2.84%. (Industry: Industrial Metals & Minerals. Alpha vs. industry at -10.92%, based on average of 40 companies)

Engages in the production, processing, and sale of coal in the United States. (Link to Alpha Natural Resources, Inc. website)

5. Arch Coal Inc. (ACI): Returned -13.7% over the last week vs. an industry average of -2.84%. (Industry: Industrial Metals & Minerals. Alpha vs. industry at -10.86%, based on average of 40 companies)

Engages in the production and sale of steam and metallurgical coal from surface and underground mines located throughout the United States As of December 31, 2010, it operated or contracted out the operation of 23 active mines; and owned or controlled approximately 4. (Link to Arch Coal Inc. website)

6. Ultra Petroleum Corp. (UPL): Returned -10.25% over the last week vs. an industry average of -1.72%. (Industry: Independent Oil & Gas. Alpha vs. industry at -8.53%, based on average of 72 companies)

Engages in the acquisition, exploration, development, production, and operation of oil and natural gas properties in the United States. (Link to Ultra Petroleum Corp. website)

7. AngloGold Ashanti Ltd. (NYSE:AU): Returned -10.44% over the last week vs. an industry average of -2.11%. (Industry: Gold. Alpha vs. industry at -8.33%, based on average of 31 companies)

Engages in the exploration and production of gold.

8. Precision Drilling Corporation (NYSE:PDS): Returned -10.52% over the last week vs. an industry average of -2.44%. (Industry: Oil & Gas Equipment & Services. Alpha vs. industry at -8.08%, based on average of 31 companies)

Provides onshore well drilling services, completion and workover services, and ancillary services to the oil and gas industry in North America and internationally.

9. San Juan Basin Royalty Trust (NYSE:SJT): Returned -9.13% over the last week vs. an industry average of -1.72%. (Industry: Independent Oil & Gas. Alpha vs. industry at -7.41%, based on average of 72 companies)

Operates as an express trust. (Link to San Juan Basin Royalty Trust website)

10. AK Steel Holding Corporation (NYSE:AKS): Returned -13.85% over the last week vs. an industry average of -6.61%. (Industry: Steel & Iron. Alpha vs. industry at -7.24%, based on average of 20 companies)

Produces flat-rolled carbon, stainless, and electrical steels, and tubular products primarily in the United States and internationally. (Link to AK Steel Holding Corporation website)

11. Walter Energy, Inc. (NYSE:WLT): Returned -9.97% over the last week vs. an industry average of -2.84%. (Industry: Industrial Metals & Minerals. Alpha vs. industry at -7.13%, based on average of 40 companies)

Produces and exports metallurgical coal for the steel industry primarily in the United States. (Link to Walter Energy, Inc. website)

12. Kronos Worldwide Inc. (NYSE:KRO): Returned -7.73% over the last week vs. an industry average of -0.69%. (Industry: Specialty Chemicals. Alpha vs. industry at -7.04%, based on average of 33 companies)

Engages in the production and marketing of titanium dioxide pigments in North America and Europe. (Link to Kronos Worldwide Inc. website)

13. Gold Fields Ltd. (NYSE:GFI): Returned -9.14% over the last week vs. an industry average of -2.11%. (Industry: Gold. Alpha vs. industry at -7.03%, based on average of 31 companies)

Engages in the acquisition, exploration, development, and production of gold properties.

14. Harmony Gold Mining Co. Ltd. (NYSE:HMY): Returned -8.87% over the last week vs. an industry average of -2.11%. (Industry: Gold. Alpha vs. industry at -6.76%, based on average of 31 companies)

Engages in underground and surface gold mining operations in South Africa and Papua New Guinea.

15. Nabors Industries Ltd. (NYSE:NBR): Returned -7.72% over the last week vs. an industry average of -1.18%. (Industry: Oil & Gas Drilling & Exploration. Alpha vs. industry at -6.54%, based on average of 52 companies)

Operates as a land drilling contractor worldwide.

16. Bill Barrett Corp. (NYSE:BBG): Returned -7.61% over the last week vs. an industry average of -1.18%. (Industry: Oil & Gas Drilling & Exploration. Alpha vs. industry at -6.43%, based on average of 52 companies)

Engages in the exploration, development, and production of natural gas and crude oil principally in the Rocky Mountain region of the United States. (Link to Bill Barrett Corp. website)

17. Tanzanian Royalty Exploration Corp. (NYSEMKT:TRX): Returned -8.46% over the last week vs. an industry average of -2.11%. (Industry: Gold. Alpha vs. industry at -6.35%, based on average of 31 companies)

Engages in the acquisition and exploration of mineral properties in Africa.

Disclosure: I have no positions in any stocks mentioned, and no plans to initiate any positions within the next 72 hours.

Stocks: BPT, ZAZA, PBTZQ, ARCH, UPLMQ, AU, PDS, SJT, AKS, WLT, KRO, GFI, HMY, NBR