Form of 6.75% Bonds Due 2028

Unless this certificate is presented by an authorized representative of The Depository Trust Company, a New York Corporation (“DTC”), to Issuer or its agent for registration of transfer, exchange, or payment, and any certificate issued is registered in the name of Cede & Co. or in such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein.

This Security is a Book-Entry Security within the meaning of the Indenture hereinafter referred to and is registered in the name of a Depositary or a nominee thereof. This Security may not be transferred to, or registered or exchanged for Securities registered in the name of, any Person other than the Depositary or a nominee thereof and no such transfer may be registered, except in the limited circumstances described in the Indenture. Every Security authenticated and delivered upon registration of transfer of, or in exchange for or in lieu of, this Security shall be a Book-Entry Security subject to the foregoing, except in such limited circumstances described in the Indenture.

No. R-        (U.S.) $______________ CUSIP# 022249AU0

Aluminum Company of America, a corporation duly organized and existing under the laws of Pennsylvania (herein called the “Company”, which term includes any successor Person under the Indenture referred to on the reverse hereof), for value received, hereby promises to pay to Cede & Co., or registered assigns the principal sum of (United States) Dollars on January 15, 2028, and to pay interest thereon from January 27, 1998, or from the most recent January 15 or July 15 (each, an “Interest Payment Date”) to which interest has been paid or duly provided for, commencing July 15, 1998, at the rate of 6.75% per annum, until the principal hereof is paid or made available for payment. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in such Indenture, be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on the January 1 or July 1, as the case may be, next preceding such Interest Payment Date (each, a “Regular Record Date”). Except as otherwise provided in the Indenture, any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and may either be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Securities of this series may be listed, and upon such notice as may be required by such exchange, all as more fully provided in said Indenture. Payment of the principal of and any premium and interest on this Security will be made (a) at the Corporate Trust Office of the Trustee or such other office or agency of the Company as may be designated by it for such purpose in the Borough of Manhattan, The City of New York, in such coin or currency of the United States of America as at the time of payment shall be legal tender for the payment of public and private debts or (b) subject to any laws or regulations applicable thereto and to the right of the Company (limited as provided in the Indenture) to rescind the designation of any such Paying Agent, at the main offices of Pittsburgh, Pennsylvania, or at such other offices or agencies as the Company may designate, by United States dollar check drawn on, or transfer to a United States dollar account maintained by the payee with, a bank in The City of New York provided, however, that at the option of the Company payment of interest may be made by United States dollar check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register.

Reference is hereby made to the further provisions of this Security set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof, directly or through an Authenticating Agent, by manual signature of an authorized signatory, this Security shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed under its corporate seal.

Dated: January 27, 1998

This Security is one of a duly authorized issue of securities of the Company (herein called the “Securities”), issued and to be issued in one or more series under an Indenture, dated as of September 30, 1993 (herein called the “Indenture”), between the Company and PNC Bank, National Association, as Trustee (herein called the “Trustee”, which term includes any successor trustee under the Indenture), to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Holders of the Securities and of the terms upon which the Securities are, and are to be, authenticated and delivered. This Security is one of the series designated on the face hereof, currently limited in aggregate principal amount to (U.S.) $300,000,000.

The Bonds are redeemable, in whole or in part, at the option of the Company at any time at a redemption price equal to the greater of (i) 100% of the principal amount of such Bonds or (ii) as determined by a Quotation Agent (as defined herein), the sum of the present values of the remaining scheduled payments of principal and interest thereon (not including any portion of such payments of interest accrued as of the date of redemption) discounted to the date of redemption on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Adjusted Treasury Rate (as defined herein) plus 15 basis points plus, in each case, accrued interest thereon to the date of redemption. The Bonds are not convertible or exchangeable into any other security of the Company.

If an Event of Default with respect to Securities of this series shall occur and be continuing, the principal of the Securities of this series may be declared due and payable in the manner and with the effect provided in the Indenture.

The provisions relating to defeasance and discharge set forth in Section 1302 of the Indenture and covenant defeasance set forth in Section 1303 of the Indenture are applicable to the Securities of this series.

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Holders of the Securities of each series to be affected under the Indenture at any time by the Company and the Trustee with the consent of the Holders of 66-2/3% in principal amount of the Securities at the time Outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Securities of each series at the time Outstanding, on behalf of the Holders of all Securities of such series, to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Security shall be conclusive and binding upon such Holder and upon all future Holders of this Security and of any Security issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Security.

As set forth in, and subject to, the provisions of the Indenture, no Holder of any Security of this series will have any right to institute any proceeding with respect to the Indenture or for any remedy thereunder, unless such Holder shall have previously given to the Trustee written notice of a continuing Event of Default with respect to this series, the Holders of not less than 25% in principal amount of the Outstanding Securities of this series shall have made written request, and offered reasonable indemnity, to the Trustee to institute such proceeding as trustee, and the Trustee shall not have received from the Holders of a majority in principal amount of the Outstanding Securities of this series a direction inconsistent with such request and shall have failed to institute such proceeding within 60 days; provided, however, that such limitations do not apply to a suit instituted by the Holder hereof for the enforcement of payment of the principal of any premium or interest on this Security on or after the respective due dates expressed herein.

No reference herein to the Indenture and no provision of this Security or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of (and premium, if any) and interest on this Security at the times, place(s) and rate, and in the coin or currency, herein prescribed.

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Security is registrable in the Security Register, upon surrender of this Security for registration of transfer at the office or agency of the Company in any place where the principal of and any premium and interest on this Security are payable or, subject to any laws or regulations applicable thereto and to the right of the Company (limited as provided in the Indenture) to rescind the designation of any such transfer agent, at the main offices of the Company in Pittsburgh, Pennsylvania and in or at such other offices or agencies as the Company may designate, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Securities of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees.

The Securities of this series are issuable only in registered form, without coupons, in denominations of $1,000 and any integral multiple thereof. As provided in the Indenture and subject to certain limitations therein set forth, Securities of this series are exchangeable for a like aggregate principal amount of Securities of this series and of like tenor of a different authorized denomination, as requested by the Holder surrendering the same.

No service charge shall be made for any such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Security for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this Security is registered as the owner hereof for all purposes, whether or not this Security is overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

All terms used in this Security which are defined in the Indenture shall have the meanings assigned to them in the Indenture.