NEW YORK (

TheStreet

) -- Shares of metal and mining companies crumbled Thursday amid concerns that a slowdown in the economy would upset demand for materials.

In the mining sector,

Alpha Natural Resources

(ANR)

and

Rio Tinto

(RIO) - Get Report

were the biggest losers as Alpha Natural shares closed at $19.80, down $2.50, or 11.2%, and Rio Tinto finished at $46.07, down $5.22, or 10.2%.

Private-sector coal company

Peabody Energy

(BTU) - Get Report

dropped to $37.03, off $2.93, or 7.3%.

BHP Billiton

(BHP) - Get Report

shares slumped to $67.28, down $4.68, or 6.5%.

Newmont Mining

(NEM) - Get Report

closed at $65.24, down $2.44, or 3.6%.

Walter Energy

(WLT)

,

which lowered its coking coal sales outlook Wednesday, sending railroad stocks into a tailspin, fell to $64.10, shedding $2.15, or 3.3%

The biggest losers in metal stocks on Thursday were

AK Steel

(AKS) - Get Report

and

U.S. Steel

(X) - Get Report

as AK closed at $6.74, down 87 cents, or 11.4%, and as U.S. Steel finished at $21.99, down $2.79, or 11.2%.

ArcelorMittal

(MT) - Get Report

dropped to $15.16, off $1.31, or 8%. Dow component

Alcoa

(AA) - Get Report

was at $10.11, down 73 cents, or 6.7%. Irving, Texas-based

Commercial Metals

(CMC) - Get Report

closed at $9.91, down 55 cents, or 5.3%. Steel manufacturer

Nucor

(NUE) - Get Report

dropped on Thursday to $31.25, down $1.67, or 5.1%.

-- Written by Joe Deaux in New York.

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