EX-1 2 gl894078-ex1.txt JOINT FILING AGREEMENT SCHEDULE 13D ---------------------------- ------------------------- CUSIP No. 598709103 Page 10 of 11 ---------------------------- ------------------------- Exhibit 1 Joint Filing Agreement Pursuant to Rule 13d-1(k) The undersigned persons (the "Reporting Persons") hereby agree that a joint statement on this Amendment No. 4 to Schedule 13D, and any amendments thereto, is to be filed. Each of the Reporting Persons is responsible for the completeness and accuracy of the information concerning each of them contained therein, but none of the Reporting Persons is responsible for the completeness or accuracy of the information concerning any other Reporting Person. Date: April 11, 2006 GLENCORE FINANCE AG By: /s/ Steven Isaacs ---------------------------------------- Name: Steven Isaacs Title: Director By: /s/ Barbara Wolfensberger Name: Barbara Wolfensberger Title: Director GLENCORE INTERNATIONAL AG By: /s/ Lotti Grenacher ---------------------------------------- Name: Lotti Grenacher Title: Officer By: /s/ Andreas Hubmann ---------------------------------------- Name: Andreas Hubmann Title: Officer SCHEDULE 13D ---------------------------- ------------------------- CUSIP No. 598709103 Page 11 of 11 ---------------------------- ------------------------- GLENCORE HOLDING AG By: /s/ Willy R. Strothotte ---------------------------------------- Name: Willy R. Strothotte Title: Chairman By: /s/ Ivan Glasenberg ---------------------------------------- Name: Ivan Glasenberg Title: Director