6-K

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SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

Form 6-K

Report of Foreign Private Issuer
Pursuant to Rule 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

For the month of: May, 2005 Commission File Number: 333-124186-02

HUDBAY MINERALS INC.
(Name of Registrant)

201 Portage Avenue, Suite 1906
Winnipeg, Manitoba
Canada R3B 3L3
(Address of Principal Executive Offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

Form 20-F o                        Form 40-F o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):                              

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):                              

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes o                        No ý

If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):

SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	HUDBAY MINERALS INC.
Date: May 4, 2005	By:	/s/  BRIAN DONALD GORDON Name: Brian Donald Gordon Title: Vice President and General Counsel

EXHIBIT INDEX

Exhibit	Description of Exhibit
99.1	Material Change Report dated April 23, 2005

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SIGNATURES
EXHIBIT INDEX

EX-99.1

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EXHIBIT 99.1

FORM 51-102F3
MATERIAL CHANGE REPORT

Item 1    Name and Address of Company

HudBay Minerals Inc.
6 Adelaide Street East
Suite 300
Toronto, Ontario M5C 1H6

Item 2    Date of Material Change

April 18, 2005.

Item 3    News Release

A press release concerning this material change was issued on April 18, 2005 through the Canadian disclosure network.

Item 4    Summary of Material Changes

HudBay Minerals Inc. (the "Company") announced the resignation of John Knowles from the position of Vice President and Chief Financial Officer, effective as of June 30, 2005.

Item 5    Full Description of Material Change

The Company announced the resignation of John Knowles from the position of Vice President and Chief Financial Officer, effective as of June 30, 2005.

The Company is initiating a search for a replacement and will announce the new Chief Financial Officer when the process is complete.

Item 6    Reliance on subsection 7.1(2) or (3) of National Instrument 51-102

N/A.

Item 7    Omitted Information

N/A.

Item 8    Executive Officer

Brian D. Gordon, the Vice President and General Counsel of the Corporation at (416) 913-7601.

Item 9    Date of Report

April 23, 2005.

HUDBAY MINERALS INC.
By:	"Signed" Brian D. Gordon Vice President and General Counsel

2

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FORM 51-102F3 MATERIAL CHANGE REPORT