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. 6)*
Minerals
Technologies Inc.
(Name
of
Issuer)
Common
Stock
(Title
of
Class of Securities)
603158106
(CUSIP
Number)
31
December 2007
(Date
of
Event Which Requires Filing of this Statement)
Check
the
appropriate box to designate the rule pursuant to which this
Schedule
is
filed:
x
Rule
13d-1(b)
o
Rule
13d-1(c)
o
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
6
| CUSIP No. 603158106 |
Schedule
13G
|
Page
2 of 6
Pages
|
|
1
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NAMES
OF REPORTING PERSONS
I.R.S.
IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
M&G
Investment Management Limited
No
I.R.S Identification Number
|
||
|
2
|
CHECK
THE APPROPRIATE BOX IF THE MEMBER OF A GROUP*
(a)
o
(b)
o
|
||
|
3
|
SEC
USE ONLY
|
||
|
4
|
CITIZENSHIP
OR PLACE OF ORGANIZATION
United
Kingdom, England
|
||
|
NUMBER
OF
SHARES
BENEFICIALLY
OWNED
BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE
VOTING POWER
0
|
|
|
6
|
SHARED
VOTING POWER
1,552,958
|
||
|
7
|
SOLE
DISPOSITIVE POWER
0
|
||
|
8
|
SHARED
DISPOSITIVE POWER
2,889,472
|
||
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,889,472
|
||
|
10
|
CHECK
BOX IF AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
o
|
||
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
14.98%
|
||
|
12
|
TYPE
OF REPORTING PERSON
IA
|
||
Page
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| CUSIP No. 603158106 |
Schedule
13G
|
Page 3
of 6
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)
o
(b)
o
|
||
|
3
|
SEC
USE ONLY
|
||
|
4
|
CITIZENSHIP
OR PLACE OF ORGANIZATION
United
Kingdom, England
|
||
|
NUMBER
OF
SHARES
BENEFICIALLY
OWNED
BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE
VOTING POWER
0
|
|
|
6
|
SHARED
VOTING POWER
1,552,958
|
||
|
7
|
SOLE
DISPOSITIVE POWER
0
|
||
|
8
|
SHARED
DISPOSITIVE POWER
1,552,958
|
||
|
9
|
AGGREGATE
AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,552,958
|
||
|
10
|
CHECK
BOX IF AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
o
|
||
|
11
|
PERCENT
OF CLASS REPRESENTED BY AMOUNT IN ROW 9
8.05%
|
||
|
12
|
TYPE
OF REPORTING PERSON
OO
|
||
Page 3
of
6
| CUSIP No. 603158106 |
Schedule
13G
|
Page 4
of 6
Pages
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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:
1.
M&G Investment Management Limited (MAGIM)
2.
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:
(e)
MAGIM
is an investment advisor in accordance with
s.240.13d-1(b)(1)(ii)(E)
Some
of
the securities covered by this report are owned legally by Vanguard precious
Metals and Mining Fund, MAGIM’s investment advisory client. MAGIM has sole
investment power and no voting power in these securities.
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 MAGIM’s Investment
advisory clients, 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 own 2,889,472
shares
of the Issuer.
(b)
Percent of Class: 14.98%
(c)
Number of shares as to which such person has:
M&G
Investment Funds (1)
(i)
sole
power to vote or to direct the vote 0
(ii)
shared power to vote or to direct the vote
1,552,958
(iii)
sole power to dispose or to direct the disposition
of 0
(iv)
shared power to dispose or to direct the disposition
of 1,552,958
M&G
Investment Management Limited
(i)
sole
power to vote or to direct the vote 0
(ii)
shared power to vote or to direct the vote
1,552,958
(iii)
sole power to dispose or to direct the disposition
of 0
(iv)
shared power to dispose or to direct the disposition
of 2,889,472
Page
4 of 6
| CUSIP No. 603158106 |
Schedule
13G
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Page 5
of 6
Pages
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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
[
]
Item
6.
Ownership of More than Five Percent on Behalf of Another Person.
[
]
Item
7.
Identification and Classification of the Subsidiary Which Acquired
the Security Being Reported on by the Parent Holding Company.
[
]
Item
8.
Identification and Classification of Members of the Group.
Not
Applicable
Item
9.
Notice of Dissolution of Group.
Not
Applicable
Page 5
of
6
| CUSIP No. 603158106 |
Schedule
13G
|
Page 6
of 6
Pages
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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 13, 2008
Page
6 of 6
Exhibit
A
AGREEMENT
OF JOINT FILING
In
accordance with Rule 13d-1(k) under the Securities Exchanges Act of 1934,
as
amended, the undersigned hereby agrees that the foregoing statement on Schedule
13G/A, is filed on behalf of each of the undersigned without the necessity
of
filing additional joint acquisition statements. The undersigned acknowledge
that
each shall be responsible for the timely filing of such amendments, and for
the
completeness and accuracy of information concerning the others, except to
the
extent that he or it knows or has reason to believe that such information
is
inaccurate.
IN
WITNESS WHEREOF, the undersigned hereby execute this Agreement on the
13th
day of
February, 2008.
|
M&G
INVESTMENT MANAGEMENT LIMITED
|
|
| By /s/ Mark Thomas | |
| Date: February 13, 2008 | Head of Group Funds |
|
M&G
Investment Funds 1
|
|
| By /s/ Mark Thomas | |
| Date: February 13, 2008 | Head of Group Funds |