SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                  SCHEDULE 13G
                                 (Rule 13d-102)

             INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
            TO RULES 13d-1(b),(c), AND (d) AND AMENDMENTS THERETO FILED
                             PURSUANT TO RULE 13d-2(b)
                                (Amendment No. 10)*


                              Minerals Technologies Inc.
--------------------------------------------------------------------------------
                                (Name of Issuer)


                                   Common Stock
--------------------------------------------------------------------------------
                         (Title of Class of Securities)


                                     603158106
--------------------------------------------------------------------------------
                                 (CUSIP Number)


                                    26 January 2010
--------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)


Check the  appropriate box to designate the rule pursuant to which this Schedule
is filed:

[ ]  Rule 13d-1(b)
[ ]  Rule 13d-1(c)
[X]  Rule 13d-1(d)

--------------------------------------------------------------------------------
1 The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities,
and for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of
the Securities Exchange Act of 1934 (the "Act") or otherwise subject
to the liabilities of that section
of the Act, but shall be subject to all other provisions of the Act
however, see the Notes.)

                         (Continued on following pages)

                                Page 1 of 5 Pages







CUSIP No. 603158106            Schedule 13G                 Page 2 of 5 Pages
          -----------        --------------

1.       NAMES OF REPORTING PERSONS
         I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

         M&G Investment Funds (1)
         No I.R.S Identification Number
--------------------------------------------------------------------------------
2.       CHECK THE APPROPRIATE BOX IF THE MEMBER OF A GROUP*
                                                                 (a)  [ ]
                                                                 (b)  [ ]
--------------------------------------------------------------------------------
3.       SEC USE ONLY
--------------------------------------------------------------------------------
4.       CITIZENSHIP OR PLACE OF ORGANIZATION
         United Kingdom, England
--------------------------------------------------------------------------------
                     5.   SOLE VOTING POWER
NUMBER OF                 0
SHARES              ------------------------------------------------------------
BENEFICIALLY         6.   SHARED VOTING POWER
OWNED BY                  930,675
EACH                ------------------------------------------------------------
REPORTING            7.   SOLE DISPOTIVE POWER
PERSON                    0
WITH                ------------------------------------------------------------
                     8.   SHARED DISPOTIVE POWER
                          930,675
--------------------------------------------------------------------------------
9.       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
         930,675
--------------------------------------------------------------------------------
10.      CHECK BOX IF AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
         SHARES*                                              [_]
--------------------------------------------------------------------------------
11.      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
         4.96%
--------------------------------------------------------------------------------
12.      TYPE OF REPORTING PERSON
         OO
--------------------------------------------------------------------------------







CUSIP No. 603158106           Schedule 13G                 Page 3 of 5 Pages
          -----------        --------------

Item 1(a).   Name of Issuer:

                  Minerals Technologies Inc.

Item 1(b).   Address of Issuer's Principal Executive Offices:

           The Chrysler Building, 405 Lexington Avenue, New York,
           NY 10174, United States

Item 2(a).   Name of Person Filing:

		   M&G Investment Funds 1

Item 2(b).   Address of Principal Business Office or, if None,
             Residence:

                  Governor's House, Laurence Pountney Hill, London, EC4R 0HH

Item 2(c).   Citizenship:

                  United Kingdom, England

Item 2(d).   Title of Class of Securities:

                  Common Stock

Item 2(e).   CUSIP Number:

                  603158106

Item 3.		Type of Person:
           M&G Investment Management Limited (MAGIM) is an investment
advisor in accordance with
           s.240.13d-1(b)(1)(ii)(E)

M&G Investment Funds 1 is an open-ended investment company with variable
capital, incorporated in England and Wales and authorized by the Financial
Services Authority.
It is not registered with the Securities and Exchange Commission
under the investment company act of 1940.

All the securities covered by this report are legally owned by M&G
investment funds 1, MAGIM's Investment advisory client,
and none are owned directly by MAGIM.

Item 4.      Ownership.
             Provide the following information regarding the aggregate
             number and percentage of the class of securities of the issuer
             identified in Item 1.

(a) Amount Beneficially Owned: M&G, in its capacity as investment manager,
        may be deemed to beneficially owned: 930,675 shares

        (b)  Percent of Class: 4.96%

        (c)  Number of shares as to which such person has:

               (i)    sole power to vote or to direct the vote  0
                                                                ----------
               (ii)   shared power to vote or to direct the
                      vote                                      930,675
                                                                ----------
               (iii)  sole power to dispose or to direct the
                      disposition of                            0
                                                                ----------
               (iv)   shared power to dispose or to direct the
                      disposition of                            930,675
                                                                ----------













CUSIP No. 603158106          Schedule 13G                 Page 4 of 5 Pages
          -----------        --------------

Item 5.      Ownership of Five Percent or Less of Class.
             If this statement is being filed to report the fact that as of the
             date hereof the reporting person has ceased to be the beneficial
             owner of more than five percent of the class of securities, check
             the following

             Yes.

Item 6.      Ownership of More than Five Percent on Behalf of Another
             Person.

             Not applicable.

Item 7.      Identification and Classification of the Subsidiary Which
             Acquired the Security Being Reported on by the Parent Holding
             Company.

             Not applicable.

Item 8.      Identification and Classification of Members of the Group.


             Not applicable.


Item 9.      Notice of Dissolution of Group.

             Not Applicable








CUSIP No. 603158106           Schedule 13G                 Page 5 of 5 Pages
          -----------         --------------


Item 10.     Certification.
             -------------

          (a) The following certification shall be included if the statement
          is filed pursuant to Rule 13d-1(b):

          "By signing below I certify that, to the best of my knowledge
          and belief, the securities referred to above were acquired
          and are held in the ordinary course of business and were not
          acquired and are not held for the purpose of or with the
          effect of changing or influencing the control of the issuer of
          the securities and were not acquired and are not held in
          connection with or as a participant in any transaction
          having that purpose or effect. "


                                    SIGNATURE


          After reasonable inquiry and to the best of my knowledge and belief,
          I certify that the information set forth in this statement is true,
          complete and correct.


                                By:  --//Mark Thomas//--
                                     --------------------------------------
                                Name:    Mark Thomas
                                Title:   Head of Group Funds
                                Date:    February 05, 2010