SCHEDULE 14A INFORMATION
Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934


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    14a-6(e)(2))
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                               Asarco Incorporated
- --------------------------------------------------------------------------------
                (Name of Registrant as Specified in Its Charter)


                            Phelps Dodge Corporation
- --------------------------------------------------------------------------------
     (Name of Person(s) Filing Proxy Statement if other than the Registrant)

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[X] No fee required.
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Notes:




                          [Letterhead of Phelps Dodge]



                                                              September 22, 1999


                                    IMPORTANT


Dear Asarco Shareholder:

         Phelps Dodge today announced that it has increased its offer for your
Asarco shares. Under our improved offer, Asarco shareholders would receive $9.00
in cash and 0.2880 shares of Phelps Dodge common stock for each Asarco share.
From any perspective our revised offer is vastly superior to the proposed
Asarco/Cyprus Amax merger. Compare for yourself:



                                                         
Increased Phelps Dodge Offers1                             Asarco/Cyprus Amax Merger
o   40% premiums                                           o  No premium
    -  Values Asarco at $25.47 per share                      -  Values Asarco at $5.00 + 1 new
       ($9.00 + 0.2880 Phelps Dodge shares)                      Asarco/Cyprus Amax share
    -  Values Cyprus Amax at $19.49 per share                 -  Values Cyprus Amax at $3.83 + 0.765
       ($6.89 + 0.2203 Phelps Dodge shares)                      new Asarco/Cyprus Amax share

o   $2.00/share annual dividend                            o  $0.20/share annual dividend
    -  Approximately 3.5% current yield                       -  Approximately 0.9% current yield

o   More upside potential based on proven                  o  More promises after years of
    track record                                              underperformance


         There is simply no comparison. Phelps Dodge's increased offer provides
you with a compelling premium, a $2.00 annual cash dividend and the opportunity
to participate in the greater upside potential resulting from the creation of a
world-class global copper company

- --------
1 Per share values based on 9/21/99 closing price for Phelps Dodge assuming
  full proration; premiums based on unaffected share prices for all three
  companies before trading was halted on the morning of 8/20/99; maintains
  Asarco/Cyprus Amax announced ratio of 0.765.





                                        2

through ownership of Phelps Dodge shares. The enhanced Phelps Dodge offer
contains an election feature that allows you to express your preference for
Phelps Dodge shares or cash. Any Phelps Dodge shares receive will continue to
be tax-free. However, you will not be able to realize the benefits from Phelps
Dodge's increased offer if the proposed Asarco/Cyprus Amax no-premium merger is
approved by shareholders.

                          Preserve your opportunity to
                 consider the financially superior Phelps Dodge
                                     offer.

                  Vote AGAINST the proposed Asarco/Cyprus Amax
             no-premium merger by signing, dating and returning the
                         enclosed BLUE proxy card today.

         It is important that you send your Board of Directors a clear message
that you want Phelps Dodge's financially superior offer. Vote AGAINST the
proposed Asarco/Cyprus Amax no-premium merger by sending in the enclosed BLUE
proxy card today. Even if you have already mailed a white proxy card, you have
every legal right to change that vote by signing, dating and mailing the
enclosed BLUE proxy card today.

Sincerely,


/s/ Douglas C. Yearley                    /s/ J. Steven Whisler
- ------------------------------------      -------------------------------------
Douglas C. Yearley                        J. Steven Whisler
Chairman and Chief Executive Officer      President and Chief Operating Officer


If you need help voting your shares AGAINST the Asarco/Cyprus Amax no-premium
merger, please call INNISFREE M&A INCORPORATED toll free at 877-750-5838.

This letter is neither an offer to exchange nor a solicitation of an offer to
exchange the common stock of Asarco or Cyprus Amax for common stock of Phelps
Dodge. The offers are being made solely by means of Phelps Dodge's amended
prospectus and related letter of transmittal which are being mailed to
shareholders separately. This letter shall not constitute an offer to sell or
the solicitation of an offer to buy nor shall there be any sale these
securities in any state in which such offer, solicitation or sale would be
unlawful prior to registration or qualification under the securities laws of
any such state.



                            PHELPS DODGE CORPORATION


Dear Shareholder:

Please accept our thanks for sending in your Blue Proxy Card.

To avoid any possible dispute as to the validity of your proxy for the reason(s)
indicated below, we are requesting that you sign, date and mail the enclosed
additional Blue Proxy Card with the correction indicated below in the
self-addressed envelope provided for your convenience. This Proxy will
automatically revoke any previously granted proxy when it is returned.

|_|   Your previous proxy was unsigned. (If signing as attorney, executor,
      administrator, personal representative of an estate, corporate officer,
      partner, trustee, custodian or guardian, please sign and give your full
      title as such.)

|_|   Your previous proxy was undated. (Please date, sign and return the
      enclosed Blue Proxy Card in the enclosed envelope.)

|_|   Your previous proxy omitted your title or authority. (If signing as
      attorney, executor, administrator, personal representative of an estate,
      corporate officer, partner, trustee, custodian or guardian, please sign
      and give your full title as such.)

|_|   Your previous proxy, as signed, did not conform to the name shown on the
      proxy. (Please date and sign the enclosed Blue proxy card exactly as the
      registration appears on the proxy, including your full title if signing
      other than in an individual capacity.) If the registration is in the name
      of a custodian for the benefit of a minor, the custodian must sign and
      indicate his/her capacity. If you are a beneficiary 18 years or older, you
      may sign as long as you indicate your age.

|_|   Your previous proxy was not signed by all joint owners. (If shares are
      registered in the name of more than one person, each such person should
      sign the enclosed Blue Proxy Card. If a joint tenant is deceased, please
      indicate that you are the surviving joint owner.)

|_|   Your previous proxy, as marked, did not clearly specify your instructions.
      Please sign, date and clearly mark your proxy.

|_|   Other____________________________________________________________________
      _________________________________________________________________________

Since time is of the essence, we would greatly appreciate your signing, dating
and mailing the enclosed Blue Proxy Card as soon as possible. Please mail it in
the envelope provided for your convenience. If you have any questions, please
call Innisfree M&A Incorporated, the firm assisting us, toll-free at
877-750-5838. Once again, we greatly appreciate your support.

Sincerely,



PHELPS DODGE CORPORATION