SUBJECT TO COMPLETION, DATED MARCH 29, 2004

PRELIMINARY PROSPECTUS SUPPLEMENT TO PROSPECTUS DATED MARCH 25, 2004

9,000,000 Shares

Common Stock

          Century Aluminum Company is offering 8,500,000 shares of its common stock. The selling shareholders are offering in the aggregate 500,000 shares. Century Aluminum Company will not receive any proceeds from the sale of shares by the selling shareholders.

          Our common stock trades on The NASDAQ Stock Market® under the symbol “CENX.” On March 26, 2004, the reported last sale price of our common stock was $28.87 per share.

          Investing in our common stock involves risks. See “Risk Factors” beginning on page S-10 of this prospectus supplement.

          We have granted the underwriters the right to purchase up to an additional 1,350,000 shares from us to cover over-allotments.

          Delivery of the shares of common stock will be made on or about                     , 2004.

          Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is                     , 2004.

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Prospectus Supplement

Prospectus

      You should rely only on the information contained in this document or to which we have referred you. Neither we nor the selling shareholders have authorized anyone to provide you with information that is different. We and the selling shareholders are offering to sell shares of our common stock only, and this document does not constitute an offer to sell, or the solicitation of any offer to buy, any securities other than the securities to which it relates. Neither we nor the selling shareholders are making an offer to sell our common stock in any jurisdiction where the offer or sale is not permitted, and this document may only be used where it is legal to sell these securities.

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      This prospectus supplement and the accompanying prospectus incorporate important business and financial information about us that is not included in or delivered with this prospectus supplement and the accompanying prospectus. We will provide without charge to each person, including any beneficial owner, to whom a prospectus supplement and the accompanying prospectus are delivered, upon written or oral request of any such person, a copy of any or all of the information that we have incorporated by reference in this prospectus supplement and the accompanying prospectus but have not delivered with this prospectus supplement and the accompanying prospectus. You may request a copy of these filings, by writing or telephoning us at: Century Aluminum Company, 2511 Garden Road, Building A, Suite 200, Monterey, CA 93940, Attention: Corporate Secretary or (831) 642-9300. See “Incorporation of Certain Documents by Reference” of this prospectus supplement.

      This prospectus supplement contains specific details regarding this offering and the accompanying prospectus contains information about our securities generally, some of which does not apply to this offering. This prospectus supplement may add, update or change information in the accompanying prospectus. To the extent that there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or any document incorporated by reference in the accompanying prospectus, on the other hand, the information contained in this prospectus supplement shall control. The information contained in this document is current only as of the date of this document.

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RISK FACTORS

      In addition to the other information included, or incorporated by reference, in this prospectus supplement and the accompanying prospectus, you should carefully consider the risks described below before making an investment. If any of the events described in the risks below actually occur, it may be difficult for us to achieve our profitability and growth goals, which could adversely affect the value of your investment in our common stock.

Risks Relating to our Business

The cyclical nature of the aluminum industry causes variability in our earnings and cash flows.

      Our operating results depend on the market for primary aluminum, which is a cyclical commodity affected by global demand and supply conditions. Historically, global demand and prices for primary aluminum have fluctuated in part due to economic and market conditions, including currency fluctuations, in the United States and other major global economies. The relative pricing of other materials, such as steel, plastic and glass, which are used as alternatives for aluminum in some applications, also affects demand for aluminum. Certain aluminum end-use markets, including the automotive sector and the building and construction sector, are also cyclical. When downturns occur in these sectors, demand for primary aluminum decreases resulting in lower prices for our products. See “The Aluminum Industry” included elsewhere in this prospectus supplement. Over the past twenty years, the average annual cash price for transactions on the LME was $0.68 per pound and has ranged from a low of $0.47 per pound in 1985 to a high of $1.15 per pound in 1988. The average LME price was $0.65 per pound for the year ended December 31, 2003. Primary aluminum prices could decline below current levels, reducing our earnings and cash flows. A prolonged downturn in prices for primary aluminum could significantly reduce the amount of cash available to us to meet our current obligations and fund our long-term business strategies.

      Conversely, if prices for primary aluminum increase, certain of our hedging transactions, including our LME-based alumina contracts, may limit our ability to take advantage of the increased prices. See “Business — Pricing and Risk Management” included elsewhere in this prospectus supplement.

Our high level of indebtedness requires significant cash flow to meet our debt service requirements, which reduces cash available for other purposes, such as the payment of dividends, and limits our ability to pursue our growth strategy.

      As of December 31, 2003, we had $344.1 million of debt and, based on the borrowing base as of that date, we would have been able to incur up to $68.1 million of additional indebtedness under our revolving credit facility, subject to customary borrowing conditions. In addition, subject to the restrictions contained in our revolving credit facility and the indenture governing the senior secured notes, we may incur significant additional debt from time to time.

      During the year ended December 31, 2003, we paid $41.3 million to meet our aggregate annual debt service requirements, including $38.2 million related to the senior secured notes. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources” included elsewhere in this prospectus supplement.

      Nordural, which we intend to acquire with a portion of the proceeds from this offering, had approximately $190 million of debt at December 31, 2003 and plans to incur additional debt over the next several years to fund an expansion of the Nordural facility. Nordural’s annual debt service requirements vary, as amounts outstanding under its senior term loan facility bear interest at a variable rate. In addition, a substantial portion of its current debt is comprised of project finance debt, which requires additional principal repayments as available cash flow increases. During the year ended December 31, 2003, Nordural paid $19.4 million in debt service.

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      The level of our indebtedness could have important consequences to you. For example, it could:

      If we complete the planned Nordural acquisition, we may also be exposed to risks of interest rate increases, because we will be responsible for the existing debt Nordural will retain after closing, substantially all of which currently bears interest at a floating rate. In addition, Nordural could use variable rate financing to fund a portion of the costs of the planned expansion of the Nordural facility.

      In addition to our indebtedness, we have liabilities and other obligations which could reduce cash available for other purposes and limit our ability to pursue our growth strategy. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources — Contractual Obligations” included elsewhere in this prospectus supplement.

Restrictive covenants in our indenture and revolving credit facility limit our ability to incur additional debt, pay dividends and pursue our growth strategy.

      The indenture governing the senior secured notes and our revolving credit facility contain various covenants that restrict the way we conduct our business and limit our ability to incur debt, pay dividends and engage in transactions such as acquisitions and investments, which may impair our ability to pursue our growth strategy. Any failure to comply with those covenants may constitute a breach under the indenture or the revolving credit facility, which may result in the acceleration of all or a substantial portion of our outstanding indebtedness and termination of commitments under our revolving credit facility. If our indebtedness is accelerated, we may be unable to repay those amounts upon acceleration. Our senior secured notes are secured by a substantial portion of the assets comprising our Ravenswood and Hawesville facilities and all our inventory and accounts receivable have been pledged to secure borrowings under our revolving credit facility. If the secured lenders compel the sale of those assets or our company is liquidated for any other reason, our secured lenders would have to be repaid before proceeds from the sale of those assets would be available to repay our unsecured creditors and for distribution to our equity holders.

      We will require a waiver or amendment of our revolving credit facility to complete the Nordural acquisition. We do not expect that we will require an amendment to our indenture to permit the acquisition. We intend to treat Nordural as an “unrestricted” subsidiary under the indenture that would not be subject to the covenants.

      Nordural has a senior term loan facility that contains covenants, including financial and customary “project finance” covenants, that restrict the way Nordural conducts its business. If we complete the Nordural acquisition, these covenants will limit Nordural’s ability to pay dividends to us, incur debt and engage in transactions such as acquisitions. If Nordural is unable to comply with these covenants, the lenders would be able to cancel commitments under Nordural’s loan facility, cause all or part of the amounts outstanding under the loan facility to be immediately due and payable and foreclose on any collateral securing the loan facility. All of Nordural’s shares and assets have been pledged to secure its obligations under the loan facility. We intend to obtain additional financing for Nordural to facilitate its expansion, the terms of which have not yet been determined. The restrictions imposed by such additional financing may be materially more restrictive than those contained in Nordural’s existing loan facility.

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We have reduced our casting and shipping costs by selling molten aluminum to major customers located adjacent to our Ravenswood and Hawesville facilities; the loss of one of these major customers would increase our production costs at those facilities.

      We derived a combined total of 51% of our consolidated net sales for 2003 from Pechiney, S.A. and Southwire Company. Pechiney’s facility is located adjacent to our Ravenswood facility and Southwire’s facility is located adjacent to our Hawesville facility. Due to this proximity, we are able to deliver molten aluminum to these customers, thereby eliminating our casting and shipping costs and our customers’ remelting costs. We have long-term contracts with Pechiney and Southwire which are due to expire at various times from 2005 through 2011. Pechiney has the right to reduce its purchases from us by 50%, upon twelve months’ notice, and Southwire has the right to reduce its purchases from us by 20% beginning in 2009. These contracts also include customary termination provisions that could result in their early termination and we may be unable to extend or replace these contracts when they terminate. If we are unable to renew these contracts when they expire, or if either customer significantly reduces its purchases from us, we will incur higher casting and shipping costs. Alcan has agreed with the U.S. Department of Justice to sell the Pechiney rolling mill that purchases molten aluminum from our Ravenswood facility in connection with its merger with Pechiney. While any buyer of the rolling mill would be expected to assume Pechiney’s obligations under our existing contract with Pechiney, we may require different terms or terminate that contract if the buyer is not deemed to be creditworthy.

A material change in our relationship with Glencore could affect how we purchase raw materials, sell our products and hedge our exposure to metal price risk.

      We benefit from our relationship with Glencore, our largest shareholder. We have entered into various long-term contracts with Glencore to sell 13.4% of our annual primary aluminum production and to purchase 53.5% of our annual alumina requirements under contracts expiring at various dates from 2006 through 2013. See “Business — Facilities” and “Business — Sales and Distribution” included elsewhere in this prospectus supplement. We also enter into forward sales and hedging contracts with Glencore, which help us manage our exposure to fluctuating aluminum prices. Because Glencore is a major customer, supplier and metal hedge counterparty, a material change in our relationship with Glencore, including any significant change in its investment in our company, could affect how we purchase raw materials, sell our products and hedge our exposure to metal price risk, which could impact our operating costs.

Glencore owns a large percentage of our common stock and can influence matters requiring shareholder approval.

      After this offering and the conversion of the convertible preferred stock, Glencore will own           % of our outstanding common stock. As a result of Glencore’s significant ownership of our common stock, Glencore has the ability to influence the outcome of matters requiring shareholder approval, including delaying or preventing a change in control. Willy R. Strothotte, the chairman of Glencore’s board of directors, serves as one of our eight directors. Craig A. Davis, our chairman and chief executive officer, is also a Glencore director. As a result of their service to us in their respective positions, Messrs. Strothotte and Davis have the ability to influence our management.

Losses caused by disruptions in the supply of power would reduce the profitability of our operations.

      We may incur losses due to a temporary or prolonged interruption of the supply of electrical power to our facilities, which can be caused by unusually high demand, blackouts, equipment failure, natural disasters or other catastrophic events. We use large amounts of electricity to produce primary aluminum, and any loss of power which causes an equipment shutdown can result in the hardening or “freezing” of molten aluminum in the pots where it is produced. If this occurs, we may experience significant losses if

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Changes or disruptions to our current alumina supply arrangements could increase our raw material costs.

      We depend on a limited number of suppliers for alumina, the principal raw material used to produce primary aluminum. Supply of alumina has been constrained over the past 18 months, and the construction of new production facilities would require substantial lead time. Disruptions to our supply of alumina could occur for a variety of reasons, including disruptions of production at a particular supplier’s alumina refinery. These disruptions may require us to purchase alumina on less favorable terms than under our current agreements. Spot alumina prices are currently substantially higher than the prices we pay under our long-term agreements.

      All of the alumina used at the Hawesville facility is currently purchased at LME-based prices under contracts with an affiliate of Kaiser Aluminum & Chemical Corporation that expire at the end of 2008. Kaiser filed for bankruptcy under Chapter 11 of the Bankruptcy Code in February 2002. Subsequent to that date, and with bankruptcy court approval, Kaiser agreed to assume our alumina supply agreement and agreed to a new alumina supply agreement for the Hawesville facility for the years 2006 through 2008. To date, Kaiser has continued to supply alumina to us pursuant to the terms of its agreement. In June 2003, Kaiser announced it was exploring the sale of several of its facilities, including Gramercy. We, together with a partner, are considering purchasing that facility and the related bauxite operations in Jamaica. Any sale by Kaiser would be subject to bankruptcy court approval. If we were to acquire the Gramercy facility, the price we would pay for alumina used by the Hawesville facility would be based on the cost of alumina production, rather than the LME price for primary aluminum. Those production costs may be materially higher than our LME-based contract price, especially in periods when aluminum prices are low and natural gas prices are high.

      If we do not acquire the Gramercy facility, and Kaiser or a successor fails to continue to supply alumina to us under the terms of our existing contracts, our costs for alumina could increase substantially, and we may be unable to fully recover damages resulting from breach of those contracts.

Changes in the relative cost of certain raw materials and energy compared to the price of primary aluminum could affect our operating results.

      Our operating results are sensitive to changes in the price of primary aluminum and the raw materials used in our production. Although we attempt to mitigate the effects of such price fluctuations through the use of various fixed-price commitments and financial instruments, these efforts may limit our ability to take advantage of favorable changes in the market prices for primary aluminum or raw materials. See “Business — Pricing and Risk Management” included elsewhere in this prospectus supplement for a discussion of these contracts in more detail.

      Electricity represents our single largest operating cost. As a result, the availability of electricity at affordable prices is crucial to the profitability of our operations. While we purchase virtually all of our electricity for our existing facilities under fixed-price contracts, a portion of the contracted cost of the electricity supplied to the Mt. Holly facility varies with our supplier’s fuel costs. An increase in our supplier’s fuel costs would increase the price the Mt. Holly facility pays for electricity. The fixed price portions of our current power contracts are due to expire at various times from 2005 through 2010. If we are unable to obtain power at affordable rates upon the expiration of these contracts, we may be forced to

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We are subject to the risk of union disputes.

      The hourly employees at the Ravenswood and Hawesville facilities are represented by the United Steel Workers of America, or USWA, and are employed under labor contracts that expire in 2006. Nordural’s employees are represented by unions and are employed under a contract that expires at the end of 2004. We may be unable to satisfactorily renegotiate those labor contracts when they expire. In addition, existing labor contracts may not prevent a strike or work stoppage at any of these facilities in the future, and any such work stoppage could prevent or significantly impair our ability to conduct production operations at those facilities.

We depend on key management personnel.

      Our management structure is streamlined and, as a result, we rely heavily on a small core senior management team. The unexpected loss of the services of one or more key employees could significantly harm our business, financial condition and operating results. The employment agreements for certain key management personnel expire at the end of 2005 and it is anticipated that several of those individuals will retire at that time.

We are subject to a variety of environmental laws that could result in costs or liabilities.

      We are obligated to comply with various federal, state and other environmental laws and regulations. If we complete our planned Nordural acquisition, we would also be required to comply with the environmental laws and regulations of Iceland and the European Economic Area with which we have no previous operational experience. Environmental laws and regulations may expose us to costs or liabilities relating to our manufacturing operations or property ownership. We incur operating costs and capital expenditures on an ongoing basis to comply with applicable environmental laws and regulations. In addition, we are currently and may in the future be responsible for the cleanup of contamination at some of our current and former manufacturing facilities. Our known liabilities with respect to compliance and cleanup, based on current information, are not expected to be material and should not adversely affect our operating results. However, if more stringent compliance or cleanup standards under environmental laws or regulations are imposed, or previously unknown environmental conditions are discovered, or if contributions from other responsible parties with respect to sites for which we have cleanup responsibilities are not available, we may be subject to additional liability, which may be material. Further, additional environmental matters for which we may be liable may arise in the future at our present sites where no problem is currently known, with respect to sites previously owned or operated by us, by related corporate entities or by our predecessors, or at sites that we may acquire in the future, including the Nordural facility. Overall production costs may become prohibitively expensive and prevent us from effectively competing in price sensitive markets if future capital expenditures and costs for environmental compliance or cleanup are significantly greater than current or projected expenditures and costs. See “Business — Environmental Matters” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources — Environmental Expenditures and Other Contingencies” included elsewhere in this prospectus supplement for a detailed description of our environmental matters and associated costs and risks.

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Acquisitions may present difficulties for us.

      We intend to use a substantial portion of the proceeds from this offering to fund the Nordural acquisition and may make other strategic acquisitions in the future. We are subject to numerous risks as a result of our acquisitions, including the following:

      Accordingly, our recent or future acquisitions might not improve our competitive position and business prospects as anticipated.

Operating in a foreign country exposes us to political, regulatory, currency and other related risks.

      The Nordural facility will be our first facility located outside of the United States. We may in the future consider other acquisitions in foreign countries. International operations may expose us to risks, including unexpected changes in foreign laws and regulations, political and economic instability, challenges in staffing and managing foreign operations, increased cost to adapt our systems and practices to those used in foreign countries, export duties, tariffs and other trade barriers, and the burdens of complying with a wide variety of foreign laws.

      In addition, we will be exposed to fluctuations in currency exchange rates and, as a result, an increase in the value of foreign currencies relative to the U.S. dollar could increase our operating expenses which are denominated and payable in those currencies. For example, Nordural’s revenues are denominated in U.S. dollars, while its labor costs are denominated in Icelandic kronur and a portion of its anode costs are denominated in euros.

The Nordural acquisition and the planned expansion of the Nordural facility are both subject to certain conditions. If we do not complete the acquisition and/or the planned expansion does not occur, our management will have broad discretion in deciding how to use the proceeds from this offering which were allocated for those purposes.

      We intend to use a substantial portion of the proceeds from this offering to fund the Nordural acquisition. The Nordural acquisition is scheduled to close after the closing of this offering, and will be subject to certain conditions. See “The Planned Nordural Acquisition.” We may also use a portion of the proceeds from this offering to fund a portion of the anticipated costs of the planned expansion of the Nordural facility, which is also subject to certain conditions. If we do not complete the acquisition and/or the planned expansion does not occur, our management will have broad discretion in deciding how to use that portion of the proceeds from this offering which were allocated for those purposes and investors will not have the opportunity to evaluate information concerning the application of those proceeds. We may use the net proceeds for working capital and other general corporate purposes, which may include debt reduction or other acquisitions.

We may not realize the expected benefits of the planned expansion of the Nordural facility.

      Nordural is planning an expansion that would double its existing production capacity. Nordural’s ability to proceed with the expansion will depend on its ability to obtain government approvals, financing and certain key contracts. Nordural has entered into non-binding Memoranda of Understanding relating to certain key contracts for the expansion, some of which do not provide the same economic benefits as its contracts for the existing capacity. We cannot assure you that Nordural, or we after closing, will complete definitive agreements with respect to these non-binding Memoranda of Understanding or that the

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      Our agreement with Columbia Ventures permits them to enter into expansion contracts prior to the closing of the acquisition after consultation with us; if we are unsatisfied with any expansion contract executed by Columbia Ventures, we have the option to terminate the acquisition agreement.

Our historical and pro forma financial information may not be comparable to our results for future periods.

      The historical and pro forma financial information included in this prospectus supplement is not necessarily indicative of our future results of operations, financial position and cash flows, and the pro forma financial information does not necessarily reflect our results of operations and financial position for the periods and dates presented. For example, our historical financial data does not reflect the effects of:

      In addition, our pro forma financial information does not include operating results from the remaining 20% interest in the Hawesville facility before we acquired it in April 2003 and may not reflect all of the effects from the integration of the financial results of the Nordural facility. Costs actually incurred following these acquisitions may be materially different from those costs reflected in the pro forma financial information. See “Unaudited Pro Forma Consolidated Financial Data” included elsewhere in this prospectus supplement.

Risks Relating to our Common Stock

Provisions in our charter documents and state law may make it difficult for others to obtain control of our company, even though some stockholders may consider it to be beneficial.

      Certain provisions of our restated certificate of incorporation and amended and restated bylaws, as well as provisions of the Delaware General Corporation Law, or DGCL, may have the effect of delaying, deferring or preventing a change of control of our company, including transactions in which our stockholders might otherwise have received a substantial premium for their shares over then current market prices. For example, these provisions:

      In addition, certain of our officers have entered into employment and severance compensation agreements that provide for cash payments, immediate vesting of stock options and performance shares and acceleration of other benefits under certain circumstances, including a change in control of our company. Our 1996 Stock Incentive Plan also provides for acceleration of the ability to exercise stock options and the vesting of performance shares upon a change of control, and our Non-Employee Directors Stock Option Plan provides for acceleration of an option holder’s ability to exercise stock options upon a change of control.

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Our stock price has been and may be volatile.

      Our common stock has experienced significant price volatility from time to time, and this volatility may continue in the future. The market price for our common stock may be affected by a number of factors, including quarterly variations in our results of operations, expectations about the future price of aluminum, changes in earnings estimates or recommendations by securities analysts, developments in our industry and sales of substantial numbers of shares of our common stock in the public market. In addition, general economic, political and market conditions and other factors unrelated to our operating performance may cause the market price of our common stock to be volatile.

FORWARD-LOOKING STATEMENTS

      In this prospectus supplement, together with the documents incorporated by reference herein, we make statements that may be considered forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. We have based these forward-looking statements on our current expectations and projections about future events. Many of these statements may be identified by the use of forward-looking words such as “anticipate,” “believe,” “hope,” “expect,” “should,” “will,” “will likely,” “forecast,” “project,” “planned,” “estimated” and “potential,” among others. These forward-looking statements are subject to risks, uncertainties and assumptions including, among other things, those described under the heading “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” of this prospectus supplement and the following:

      Given these uncertainties, you should not place undue reliance on these forward-looking statements. Also, these forward-looking statements represent our estimates and assumptions only as of the date on which they are made.

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      You should read this prospectus supplement and the accompanying prospectus, together with the documents incorporated by reference herein and therein completely and with the understanding that our actual future results may be materially different from those expressed in our forward-looking statements. We have no obligation (other than as required by law) to update or revise any of our forward-looking statements. We qualify all of our forward-looking statements by these cautionary statements.

MARKET AND INDUSTRY DATA

      We obtained the market data used throughout this prospectus supplement from our own research and from surveys or studies conducted by third parties and cited in industry or general publications, including studies prepared by CRU International Inc., an internationally recognized research firm which collects and analyzes data about the aluminum industry. Industry and general publications and surveys generally state that they have obtained information from sources believed to be reliable, but do not guarantee the accuracy and completeness of such information. While we believe that each of these studies and publications is reliable, we have not independently verified such data and do not make any representation as to the accuracy of such information. Similarly, we believe our internal research is reliable but it has not been verified by any independent sources.

USE OF PROCEEDS

      We expect to receive net proceeds from the sale of our common stock in this offering of approximately $230 million, or approximately $267 million if the underwriters exercise their over-allotment option in full. This estimate assumes an offering price of $28.87 per share, which is the reported closing price per share of our common stock as of March 26, 2004, and deductions for underwriting discounts and commissions and other estimated fees and expenses we will pay. We will not receive any proceeds from the sale of shares offered by the selling shareholders. Out of the net proceeds received by us, we intend to use:

      If the Nordural acquisition is not consummated, we intend to use the proceeds allocated for the acquisition for working capital and other general corporate purposes, which may include debt reduction or other acquisitions.

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PRICE RANGE OF COMMON STOCK

      Our common stock is quoted on the NASDAQ National Market tier of The NASDAQ Stock Market® under the symbol “CENX.” The following table sets forth the high and low reported sales prices of our common stock as reported by The NASDAQ Stock Market®.

      On March 26, 2004, the closing price per share of our common stock was $28.87. As of March 23, 2004, we had 21,211,466 shares of our common stock issued and outstanding (which were held by 28 holders of record), 1,395,089 shares reserved for issuance upon conversion of our convertible preferred stock and 1,547,973 shares reserved for issuance upon the exercise of outstanding stock options and the vesting of outstanding performance shares and restricted stock awards. Glencore has notified us that it intends to convert 500,000 shares of our outstanding convertible preferred stock that it holds upon completion of this offering.

DIVIDEND POLICY

      Since the beginning of the fourth quarter of 2002, we have not declared dividends on our common stock and suspended dividends on our preferred stock to comply with limits on dividend payments contained in the indenture governing our senior secured notes. From April 1996 through the third quarter of 2002, we declared and paid a $0.05 per share quarterly dividend on our common stock.

      The declaration of dividends on our common stock is subject to the discretion of our board of directors. The timing, amount and form of dividends, if any, depend, among other things, on our results of operations, financial condition, cash requirements and other factors deemed relevant by our board of directors. In addition, restrictions under our revolving credit facility and the indenture governing our senior secured notes limit our ability to declare and pay dividends under certain circumstances. Our revolving credit facility limits dividends on our common and preferred stock to $2.5 million per year. The indenture governing our senior secured notes limits the aggregate amount of dividends paid since the date on which the senior secured notes were issued to 50% of consolidated net income from April 1, 2001 through the most recent fiscal quarter, plus the net cash proceeds from our sales of equity securities and other amounts, including cash returns on certain investments less the aggregate amount used for the payment of dividends and other restricted payments, including investments in foreign subsidiaries. The terms of our convertible preferred stock restrict our ability to pay dividends on our common stock until all dividends have been paid on our convertible preferred stock. We plan to use a portion of the proceeds from this offering to pay all dividends on our convertible preferred stock. See “Use of Proceeds” included elsewhere in this prospectus supplement. We intend to resume the payment of dividends on our common stock when our board of directors determines we have cash available for that purpose and when permitted under the terms of our revolving credit facility, indenture and convertible preferred stock.

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CAPITALIZATION

      The following table sets forth our cash and cash equivalents and capitalization as of December 31, 2003 on an actual and as adjusted basis. The adjustments reflect:

      The table does not reflect our anticipated use of proceeds if the planned Nordural acquisition is not consummated.

      The information set forth below should be read in conjunction with the following, each of which is included elsewhere in this prospectus supplement: (1) “Use of Proceeds,” (2) “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and (3) our audited consolidated financial statements and accompanying notes.

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DILUTION

      Our net tangible book value as of December 31, 2003 was approximately            million or $           per share. Our net tangible book value per share represents our total tangible assets less total liabilities divided by the number of shares of our common stock outstanding as of December 31, 2003.

      After giving effect to the sale of                      shares of common stock offered by in this offering based on an assumed per share offering price of $                    , which is the reported closing price per share of our common stock as of April      , 2004, and deducting the estimated underwriting discount and commissions on shares sold by us and other estimated expenses related to the offering, our net tangible book value would have been approximately $           million, or $           per share. This amount represents an immediate increase in net tangible book value of $           per share to the existing stockholders and an immediate dilution of $           per share to new investors.

      If the underwriters exercise their over-allotment option in full, our net tangible book value as of December 31, 2003 would have been $           per share, representing an immediate increase to existing stockholders of $           per share and an immediate dilution of $           per share to new investors.

      The above information has been adjusted to reflect the issuance of 1,395,089 shares of our common stock upon conversion of 500,000 shares of our outstanding convertible preferred stock, which Glencore has notified us it intends to convert upon completion of this offering. The above information does not reflect 1,630,433 shares reserved for issuance, as of December 31, 2003, upon the exercise of outstanding stock options and vesting of outstanding performance shares and restricted stock awards.

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THE PLANNED NORDURAL ACQUISITION

The Stock Purchase Agreement

      On March 28, 2004, we entered into an amended and restated stock purchase agreement with Columbia Ventures Corporation to acquire 100% of the outstanding equity shares of its wholly-owned subsidiary, Nordural hf. The purchase price for the shares is $150.0 million plus cash at December 31, 2003 of $9.9 million plus an adjustment to reflect the cash flow of the business from January 1, 2004 through closing. Cash flow for this purpose is the change in net liabilities defined as total liabilities less current assets (adjusted for the inclusion of expansion capital expenditures and less advances to shareholder). The cash flow adjustment is expected to include $3.3 million for the repayment of a portion of the advances to shareholder outstanding at December 31, 2003. The agreement also provides for a contingent payment of up to $25 million to Columbia Ventures based on the completion of certain events related to the planned expansion of the facility, which may be payable as early as the closing of the acquisition.

      The stock purchase agreement contains customary representations and warranties by both parties. Columbia Ventures also has agreed to provide indemnification in certain circumstances subject to a basket of $500,000 and a cap of $15.0 million. This indemnification does not cover certain specified environmental matters.

      The Nordural acquisition, which is expected to close after the closing of this offering, is subject to the satisfaction of certain conditions. Conditions to our obligations include:

      Conditions to Columbia Ventures’ obligations include:

      The parties may terminate the stock purchase agreement as follows:

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      The stock purchase agreement provides for payment of a break-up fee to Columbia Ventures if the closing does not occur for various reasons, including our material breach of a limited number of covenants or representations. The break-up fee is $3 million or, if the agreement is terminated within 30 days before or after closing of this offering, 5% of the value of this offering.

The Nordural Facility

      Nordural is an Icelandic company that owns and operates the Nordural facility, a primary aluminum reduction facility located in Grundartangi, Iceland, approximately 25 miles northwest of Reykjavik, Iceland’s capital. It currently has an annual production capacity of approximately 198 million pounds, which would increase to approximately 397 million pounds upon completion of a planned expansion of the Nordural facility. The facility is located on two hundred acres leased by Nordural. The Nordural facility consists of an aluminum reduction plant with two potlines and casting equipment used to cast molten aluminum into ingot. The Nordural facility, built in 1998, would be our most recently constructed and lowest cost facility.

      Planned Expansion. Nordural plans to expand the Nordural facility to increase its annual production capacity to 397 million pounds, or double its current production capacity, which it estimates will cost approximately $300 million.

      The Government of Iceland. The Nordural facility operates under various long-term agreements with the Government of Iceland. These agreements include:

      In connection with the proposed expansion of the Nordural facility, Nordural has negotiated amendments to each of these agreements with the Government of Iceland, which will be signed once all of the conditions to the expansion have been satisfied.

      Power. The Nordural facility purchases power from Landsvirkjun, a power company jointly owned by the Republic of Iceland and two Icelandic municipal governments, under a contract due to expire in 2019. The power delivered to the Nordural facility under its current contract is from hydroelectric sources, a competitively-priced and renewable source of power in Iceland, at a rate based on the LME price for primary aluminum. In connection with the planned expansion, Nordural has entered into a non-binding memorandum of understanding with Sudurnes Energy and Reykjavík Energy for the supply of the additional power required for the expansion capacity. Pursuant to the memorandum of understanding, the rate for the power supplied for the expansion capacity will also be LME-based. Before the parties enter into a definitive agreement, Nordural must have financing plans in place for the expansion and the power companies must have environmental permits for the geothermal facilities to be used to provide the power to the expansion capacity. Construction of those geothermal facilities will be conditioned on the parties’ execution of a definitive agreement. Under the terms of the final power agreement, we expect that we will be required to take or pay for a significant percentage of the power to be supplied beginning a specified period after signing (subject to extension for agreed upon events) even if we have not completed construction.

      Alumina/Sales and Distribution. Nordural is party to a long-term alumina tolling contract with a subsidiary of BHP Billiton which is due to expire December 31, 2013. Under this contract, which is for virtually all of the Nordural facility’s existing production capacity, Nordural receives an LME-based fee for the conversion of alumina, supplied by BHP Billiton, into primary aluminum. The contract includes

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      Iceland is a member of the European Free Trade Area, or EFTA. EFTA countries have free trade agreements with the European Union, or EU, which provide for duty-free trade in certain industrial goods, including primary aluminum. As a result of Iceland’s EFTA membership, BHP Billiton is able to sell primary aluminum produced at the Nordural facility to EU markets on a duty-free basis, and those cost savings are reflected in the tolling fee paid to Nordural under the tolling contract.

      The following table shows the primary aluminum shipments from the Nordural facility during each of the periods indicated:

Nordural Facility Primary Aluminum Shipments(1)

      Anodes. Nordural has a contract for the supply of anodes for its existing capacity which expires in 2013. Nordural is exploring various options for anodes for the expansion capacity but does not yet have any agreements in place. While we do not yet know what terms will be agreed, we do not currently expect that the pricing will be materially different than under Nordural’s current arrangements.

      Labor. As of December 31, 2003, the Nordural facility employed 195 people, of whom 13 were hourly employees and 182 were salaried. There are six national labor unions represented in Nordural’s unionized work force. The current labor contract with these unions, which sets forth the work rules and wages for the covered employees, expires on December 31, 2004. The contract is expected to be renegotiated in the latter half of 2004. Nordural expects to hire up to 114 new employees for the planned expansion.

      Environmental. Nordural is subject to various Icelandic and other environmental laws and regulations. These laws and regulations are subject to change, which changes could result in increased costs. See “Risk Factors — We are subject to a variety of environmental laws that could result in costs or liabilities” and “Risk Factors — Operating in a foreign country exposes us to political, regulatory, currency and other related risks.” The Nordural facility, built in 1998, uses centre worked prebaked cells with automatic multiple point feeding of alumina, technology currently defined to be “best available technology” under the European Union’s Integrated Pollution Prevention and Control Directive of 1996, or IPPC. The operational restrictions for the Nordural facility, as determined by the Icelandic Minister for the Environment, are set forth in the facility’s operating license. The license currently allows for both the facility’s current and planned expansion capacity.

      Nordural Debt. As of December 31, 2003, Nordural had approximately $190 million of debt, principally consisting of debt that was originally incurred in connection with the construction of the Nordural facility in 1998 and an expansion completed in June 2001. On September 2, 2003, Nordural entered into a $185.0 million senior term loan facility with a syndicate of banks. A substantial portion of the proceeds from the loan was used to repay indebtedness outstanding under an existing $167.2 million senior facility agreement. At December 31, 2003, the balance of the loan facility was $178.3 million. Amounts borrowed under Nordural’s loan facility generally bear interest at the applicable LIBOR rate plus an initial margin of 1.45% per year, which increases to 1.55% per year in January 2010 and 1.65% in January 2014, plus an applicable percentage to cover certain lender compliance costs. Nordural is required to pay a commitment fee of 0.5% per year on undrawn amounts.

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      Columbia Ventures secured Nordural’s obligations under the loan facility by pledging all of its Nordural shares pursuant to a share pledge agreement with the lenders. In addition, all of Nordural’s assets have been pledged as security under the loan facility. Amounts outstanding under the loan facility are payable semiannually in installments through June 30, 2018. The amount of each installment is based on a scheduled rate that fluctuates between 2.74% and 3.88% semi-annually. Nordural may voluntarily prepay all or part of the loan under the facility without penalty provided it gives five business days’ notice, subject to a minimum payment threshold. The agreement provides for mandatory prepayment upon the receipt of proceeds from certain asset sales, events impairing the value of assets and insurance recoveries. If the price of aluminum falls below designated levels for six months prior to a payment date and certain debt coverage ratios are not met, the loan facility provides for deferral of principal payments. Principal payments are increased if certain debt coverage ratios are exceeded.

      Nordural’s loan facility contains customary covenants, including limitations on additional indebtedness, security interests, investments, asset sales, loans, guarantees, capital expenditures, mergers and acquisitions, amendments to various agreements used in the operation of the Nordural facility, hedging agreements, distributions and share capital redemptions. Nordural is also subject to various financial covenants, including minimum debt service coverage, loan life coverage and net worth covenants. The loan facility contains customary events of default, including nonpayment, misrepresentation, breach of a covenant, insolvency and default of other indebtedness. If an event of default were to occur, the various banks under the loan facility would have the right to cancel all commitments and demand repayment of the loan facility.

      Expansion Financing. We are considering a variety of options for financing the expansion, including project finance. We expect that project finance would have terms similar to Nordural’s existing financing arrangement, but we may enter into alternative financing on terms that could be materially different.

      Risk Management. Substantially all of Nordural revenues are derived from a tolling arrangement whereby it converts alumina provided to it into primary aluminum for a fee based on the LME price for primary aluminum. Nordural’s revenues are subject to the risk of decreases in the market price of primary aluminum; however, because it produces primary aluminum under a tolling arrangement, Nordural is not exposed to increases in the price for alumina, the principal raw material used in the production of primary aluminum. In addition, under its current power contract, Nordural purchases power at a rate which is a percentage of the LME price for primary aluminum. By linking its most significant production cost to the LME price for primary aluminum, Nordural has a natural hedge against downswings in the market for primary aluminum; however, this hedge also limits Nordural’s upside as the LME price increases.

      Nordural is exposed to foreign currency risk due to fluctuations in the value of the U.S. dollar as compared to the euro and the Icelandic krona. Under its long-term tolling agreement with BHP Billiton, which covers virtually all of Nordural’s current production, Nordural receives revenues linked to the LME price for primary aluminum, which is denominated in U.S. dollars. Nordural’s labor costs are denominated in Icelandic kronur and a portion of its anode costs are denominated in euros. As a result, an increase in the value of those currencies relative to the U.S. dollar would affect Nordural’s operating margins. See “Risk Factors — Operating in a foreign country exposes us to political, regulatory, currency and other related risks.”

      Borrowings under Nordural’s term loan facility bear interest at a margin over the applicable LIBOR rate, plus an applicable percentage to cover certain lender compliance costs. At December 31, 2003, Nordural had $183.2 million of long-term liabilities which bear interest at a variable rate.

      Nordural does not currently have any material financial instruments to hedge commodity, currency or interest rate risk. Nordural may hedge a certain amount of such risk in the future, including through the purchase of aluminum put options and interest rate swaps that would have the effect of fixing a portion of its floating rate debt.

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      Liquidity and Capital Resources. Nordural generally requires minimal working capital primarily because it receives payments under the tolling agreement that are generally received in advance of its principal payment obligations. Its principal cash need is for capital expenditures relating to its expansion, as described above, and debt service as described above. We expect Nordural will retain its internally generated cash flow and use it to finance the expansion and repay debt.

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UNAUDITED PRO FORMA CONSOLIDATED FINANCIAL DATA

      The following tables present our unaudited pro forma consolidated balance sheet as of December 31, 2003 and unaudited pro forma consolidated statement of operations for the year ended December 31, 2003. The unaudited pro forma consolidated financial data presented below has been derived from the following, which are included elsewhere in this prospectus supplement: (1) our audited consolidated financial statements and accompanying notes and (2) the separate audited financial statements and accompanying notes of Nordural for the year ended December 31, 2003. The unaudited pro forma consolidated financial data has been prepared for illustrative purposes only and does not purport to represent what our results of operations or financial condition would actually have been had the transactions described below in fact occurred as of the dates specified. In addition, the unaudited pro forma consolidated financial data does not purport to project our results of operations or financial condition as of any date or for any future period. Among other things, the unaudited pro forma consolidated financial data does not reflect the effects of our acquisition of the remaining 20% interest in its Hawesville primary aluminum reduction facility prior to the closing of that acquisition in April 2003.

      The unaudited pro forma consolidated balance sheet as of December 31, 2003 gives effect to the following events as if they were consummated on December 31, 2003:

      The unaudited pro forma consolidated statement of operations for the year ended December 31, 2003 gives pro forma effect to these events as if they were consummated on January 1, 2003.

      The Nordural acquisition would be accounted for using the purchase method of accounting. Under the purchase method of accounting, the cash payment of the estimated aggregate purchase price for Nordural (including transaction fees and expenses) would be allocated to the tangible assets, identifiable intangible assets and liabilities of Nordural, based upon their respective fair values. The allocation of the purchase price, useful lives assigned to assets and other adjustments made to the unaudited pro forma consolidated financial data are based upon available information and certain preliminary assumptions that we believe are reasonable under the circumstances. We have not yet completed the fair market value allocation to the specific assets and liabilities of Nordural. Consequently, the final amounts allocated and the related useful lives could differ from those reflected in the unaudited pro forma consolidated financial data and the effects could be material. The acquisition of Nordural is subject to certain conditions, including the successful completion of this offering, and there can be no assurance that the acquisition will be consummated.

      The unaudited pro forma consolidated financial data should be read in conjunction with the following, which are included elsewhere in this prospectus supplement: (1) our audited consolidated financial statements and accompanying notes, (2) “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and (3) the separate audited financial statements and accompanying notes of Nordural.

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UNAUDITED PRO FORMA CONSOLIDATED BALANCE SHEET

As of December 31, 2003