SCHEDULE 13G

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G
Under the Securities Exchange Act of 1934



U.S. SILICA HOLDINGS, INC.
(Name of Issuer)

COMMON STOCK, PAR VALUE $0.01 PER SHARE
(Title of Class of Securities)

90346E103
(CUSIP Number)

MARCH 23, 2015
(Date of event which requires filing of this statement)

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

     o Rule 13d-1(b)

     þ Rule 13d-1(c)

     o Rule 13d-1(d)

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 ("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).



                     
CUSIP No.
 
90346E103

SCHEDULE 13G

Page  
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15

1
 NAMES OF REPORTING PERSONS
 
 ICS Opportunities, Ltd.
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Cayman Islands
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 1,668,859
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 1,668,859
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,668,859
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 3.1%
12 TYPE OF REPORTING PERSON

 CO


                     
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SCHEDULE 13G

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1
 NAMES OF REPORTING PERSONS
 
 Integrated Assets, Ltd.
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Cayman Islands
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 77,617
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 77,617
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 77,617
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 0.1%
12 TYPE OF REPORTING PERSON

 
CO


                     
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SCHEDULE 13G

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1
 NAMES OF REPORTING PERSONS
 
 Integrated Core Strategies (US) LLC
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 1,138,965
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 1,138,965
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,138,965
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 2.1%
12 TYPE OF REPORTING PERSON

 
OO


                     
CUSIP No.
 
90346E103

SCHEDULE 13G

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1
 NAMES OF REPORTING PERSONS
 
 Millennium International Management LP
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 1,746,476
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 1,746,476
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,746,476
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 3.3%
12 TYPE OF REPORTING PERSON

 
PN


                     
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SCHEDULE 13G

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1
 NAMES OF REPORTING PERSONS
 
 Millennium International Management GP LLC
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 1,746,476
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 1,746,476
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 1,746,476
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 3.3%
12 TYPE OF REPORTING PERSON

 
OO


                     
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SCHEDULE 13G

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1
 NAMES OF REPORTING PERSONS
 
 Millennium Management LLC
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 2,885,441
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 2,885,441
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 2,885,441
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 5.4%
12 TYPE OF REPORTING PERSON

 
OO


                     
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SCHEDULE 13G

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1
 NAMES OF REPORTING PERSONS
 
 Israel A. Englander
2
 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 (a)   o
 (b)   þ
3
 SEC USE ONLY
4
 CITIZENSHIP OR PLACE OF ORGANIZATION

 United States
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
5
 SOLE VOTING POWER

 -0-
6
 SHARED VOTING POWER

 2,885,441
 
7
 SOLE DISPOSITIVE POWER

 -0-
 
8
 SHARED DISPOSITIVE POWER

 2,885,441
 
9
 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 2,885,441
10
 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

 o
11
 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 5.4%
12
 TYPE OF REPORTING PERSON

 IN

                     
CUSIP No.
 
90346E103

 SCHEDULE 13G

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Item 1.    
 
(a) Name of Issuer:
 
   
 
  U.S. Silica Holdings, Inc., a Delaware corporation (the "Issuer").
 
   
 
(b) Address of Issuer’s Principal Executive Offices:
 
   
 
 

8490 Progress Drive, Suite 300
Frederick, Maryland 21701

     
Item 2.
(a) Name of Person Filing:
 
(b) Address of Principal Business Office:
 
(c) Citizenship:
     
 
  ICS Opportunities, Ltd.
c/o Millennium International Management LP
666 Fifth Avenue
New York, New York 10103
Citizenship: Cayman Islands
 
   
 
  Integrated Assets, Ltd.
c/o Millennium International Management LP
666 Fifth Avenue
New York, New York 10103
Citizenship: Cayman Islands
 
   
 
  Integrated Core Strategies (US) LLC
c/o Millennium Management LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Millennium International Management LP
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Millennium International Management GP LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Millennium Management LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: Delaware
 
   
 
  Israel A. Englander
c/o Millennium Management LLC
666 Fifth Avenue
New York, New York 10103
Citizenship: United States
 
   
  (d) Title of Class of Securities:
common stock, par value $0.01 per share ("Common Stock")
 
  (e) CUSIP Number:
     
    90346E103


                     
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SCHEDULE 13G

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Item 3.  If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b), check whether the person filing is a:

 
  (a)   o   Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
             
 
  (b)   o   Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
             
 
  (c)   o   Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
             
 
  (d)   o   Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
             
 
  (e)   o   An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);
             
 
  (f)   o    An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

                     
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 SCHEDULE 13G

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  (g)   o   A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);
             
 
  (h)   o   A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
             
 
  (i)   o   A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
             
 
  (j)   o   Group, in accordance with §240.13d-1(b)(1)(ii)(J).

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

   As of the close of business on March 30, 2015:

   i) ICS Opportunities, Ltd., an exempted limited company organized under the laws of the Cayman Islands ("ICS Opportunities"), beneficially owned 1,668,859 shares of the Issuer’s Common Stock; and

   ii) Integrated Assets, Ltd., an exempted limited company organized under the laws of the Cayman Islands ("Integrated Assets"), beneficially owned 77,617 shares of the Issuer’s Common Stock; and

   iii) Integrated Core Strategies (US) LLC, a Delaware limited liability company ("Integrated Core Strategies"), beneficially owned 1,138,965 shares of the Issuer’s Common Stock.

   Millennium International Management LP, a Delaware limited partnership ("Millennium International Management"), is the investment manager to ICS Opportunities and Integrated Assets and may be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities and Integrated Assets.

   Millennium International Management GP LLC, a Delaware limited liability company ("Millennium International Management GP"), is the general partner of Millennium International Management and may also be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities and Integrated Assets.

   Millennium Management LLC, a Delaware limited liability company ("Millennium Management") is the general partner of the 100% shareholder of ICS Opportunities and Integrated Assets and may be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities and Integrated Assets. Millennium Management is also the general partner of the managing member of Integrated Core Strategies and may be deemed to have shared voting control and investment discretion over securities owned by Integrated Core Strategies.

   Israel A. Englander, a United States citizen ("Mr. Englander"), is the managing member of Millennium International Management GP and Millennium Management and may also be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities, Integrated Assets and Integrated Core Strategies.

   The foregoing should not be construed in and of itself as an admission by Millennium International Management, Millennium International Management GP, Millennium Management or Mr. Englander as to beneficial ownership of the securities owned by ICS Opportunities, Integrated Assets or Integrated Core Strategies, as the case may be.

(b) Percent of Class:   

   As of the close of business on March 30, 2015, Millennium Management and Mr. Englander may be deemed to have beneficially owned 2,885,441 shares or 5.4% of the Issuer’s Common Stock outstanding (see Item 4(a) above), which percentage was calculated based on 53,352,248 shares of Common Stock outstanding as of March 9, 2015, as per the Issuer’s Proxy Statement dated March 27, 2015.


                     
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 (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

   2,885,441 (See Item 4(b))

 (iii) Sole power to dispose or to direct the disposition of

   -0-

(iv) Shared power to dispose or to direct the disposition of

   2,885,441 (See Item 4(b))

Item 5. Ownership of Five Percent or Less of a 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 o .

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

    See Exhibit I.

Item 9. Notice of Dissolution of Group

    Not applicable.

Item 10. Certification 

   By signing below each of the undersigned certifies that, to the best of its knowledge and belief, the securities referred to above 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.


                     
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Exhibits:

Exhibit I: Joint Filing Agreement, dated as of March 30, 2015, by and among ICS Opportunities, Ltd., Integrated Assets, Ltd., Integrated Core Strategies (US) LLC, Millennium International Management LP, Millennium International Management GP LLC, Millennium Management LLC and Israel A. Englander.


                     
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SCHEDULE 13G

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SIGNATURE

             

After reasonable inquiry and to the best of its knowledge and belief, each of the undersigned certifies that the information with respect to it set forth in this statement is true, complete, and correct.

Dated: March 30, 2015

ICS OPPORTUNITIES, LTD.

By: Millennium International Management LP,
       its Investment Manager

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED ASSETS, LTD.

By: Millennium International Management LP,
       its Investment Manager

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED CORE STRATEGIES (US) LLC

By: Integrated Holding Group LP,
       its Managing Member

By: Millennium Management LLC,
       its General Partner

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT LP

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT GP LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM MANAGEMENT LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

/s/ Israel A. Englander by David Nolan
pursuant to Power of Attorney filed with
the SEC on June 6, 2005

Israel A. Englander



                     
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SCHEDULE 13G

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      EXHIBIT I              
                     
      JOINT FILING AGREEMENT              

This will confirm the agreement by and among the undersigned that the Schedule 13G filed with the Securities and Exchange Commission on or about the date hereof with respect to the beneficial ownership by the undersigned of the Common Stock, par value $0.01 per share, of U.S. Silica Holdings, Inc., a Delaware corporation, will be filed on behalf of each of the persons and entities named below in accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

Dated: March 30, 2015

ICS OPPORTUNITIES, LTD.

By: Millennium International Management LP,
       its Investment Manager

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED ASSETS, LTD.

By: Millennium International Management LP,
       Investment Manager

By: /s/ David Nolan

Name: David Nolan
Title:  Vice Chairman

 

INTEGRATED CORE STRATEGIES (US) LLC

By: Integrated Holding Group LP,
       its Managing Member

By: Millennium Management LLC,
       its General Partner

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT LP

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM INTERNATIONAL MANAGEMENT GP LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

MILLENNIUM MANAGEMENT LLC

By: /s/David Nolan

Name: David Nolan
Title:  Vice Chairman

 

/s/ Israel A. Englander by David Nolan
pursuant to Power of Attorney filed with
the SEC on June 6, 2005

Israel A. Englander