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


Filed by the Registrant [ ]
Filed by a Party other than the Registrant [ X ]

Check the appropriate box:

[ ] Preliminary Proxy Statement
[ ] Confidential, for Use of the Commission Only (as permitted by Rule
    14a-6(e)(2))
[ ] Definitive Proxy Statement
[X] Definitive Additional Materials
[ ] Soliciting Material Pursuant to ss.240.14a-11(c) or ss.240.14a-12


                          Cyprus Amax Minerals Company
- --------------------------------------------------------------------------------
                (Name of Registrant as Specified in Its Charter)


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

Payment of Filing Fee (Check the appropriate box):
[X]  No fee required.
[ ]  $125 per Exchange Act Rules O-11(c)(1)(ii), 14a-6(i)(1), 14a-6(i)(2) or
     Item 22(a)(2) of Schedule 14A.
[ ]  Fee computed on table below per Exchange Act Rules 14a-6(i)(4) and 0-11.

         1) Title of each class of securities to which transaction applies:

            --------------------------------------------------------------------

         2) Aggregate number of securities to which transaction applies:

            --------------------------------------------------------------------

         3) Per unit price or other underlying value of transaction computed
            pursuant to Exchange Act Rule 0-11 (set forth the amount on
            which the filing fee is calculated and state how it was
            determined):

            --------------------------------------------------------------------

         4) Proposed maximum aggregate value of transaction:

            --------------------------------------------------------------------

         5) Total fee paid:

            --------------------------------------------------------------------

[ ]      Fee paid previously by written preliminary materials.
[ ]      Check box if any part of the fee is offset as provided by
         Exchange Act Rule 0-11(a)(2) and identify the filing for which
         the offsetting fee was paid previously. Identify the previous
         filing by registration statement number, or the Form or Schedule
         and the date of its filing.

         1)     Amount Previously Paid:_________________________________________
         2)     Form, Schedule or Registration Statement No.:-__________________
         3)     Filing Party:___________________________________________________
         4)     Date Filed:_____________________________________________________
Notes:




September 23, 1999

ATTENTION ASARCO AND CYPRUS AMAX SHAREHOLDERS:

NOW THERE'S NO COMPARISON

PHELPS DODGE has increased its offers for ASARCO and Cyprus Amax and added a
substantial CASH component. Compare for yourself:



                                                           
INCREASED PHELPS DODGE OFFERS                                 ASARCO/CYPRUS AMAX MERGER

- - 40 % premiums                                               - NO premium
     - Values ASARCO at $25.90 per share                           - Values ASARCO at $5.00 + 1 new
       ($9.00 + 0.2880 Phelps Dodge shares)                          ASARCO/Cyprus Amax share
     - Values Cyprus Amax at $19.82 per share                      - Values Cyprus Amax at $3.83 + 0.765
       ($6.89 + 0.2203 Phelps Dodge shares)                          new ASARCO/Cyprus Amax share

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

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



There is simply no comparison. Tell your Boards you want Phelps Dodge's superior
offers. Vote NO to the ASARCO/Cyprus Amax NO-premium merger by sending in your
BLUE ASARCO and GOLD Cyprus Amax proxy cards.

- --------------------------------------------------------------------------------
Only your most recent vote counts -- so it's not too late to vote AGAINST the
ASARCO/Cyprus Amax NO-premium merger. If you need help voting your shares,
please call INNISFREE M&A INCORPORATED toll free at 877-750-5838.
- --------------------------------------------------------------------------------

[PHELPS DODGE CORPORATION LOGO]

NOTE: Per share values based on 9/22/99 closing share 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 exchange ratio of 0.765.

This advertisement 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 will be made solely by means of Phelps Dodge's
Prospectus and the related Letter of Transmittal.





This advertisement shall not constitute an offer to sell or the solicitation of
an offer to buy nor shall there be any sale of 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.