SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Shinn Bryan Adair (Last) (First) (Middle) C/O US SILICA HOLDINGS INC. 24275 KATY FREEWAY SUITE 600 (Street) KATY TX 77494 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol U.S. SILICA HOLDINGS, INC. [ SLCA ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner X Officer (give title below) Other (specify below) CEO
	3. Date of Earliest Transaction (Month/Day/Year) 04/01/2021
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	04/01/2021		M(1)		13,119	A	$0.00	845,150	D
Common Stock	04/01/2021		F(2)		5,163	D	$13.02	839,987(3)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock	(4)	04/01/2021		M			13,119	(5)	(5)	Common Stock	13,119	$0.00	0	D

Explanation of Responses:

1. Scheduled vesting of restricted stock units granted on April 1, 2018.

2. Represents tax withholding on vested restricted stock units.

3. Includes (i) 40,666 restricted stock units granted on February 12, 2019 which will vest on February 12, 2022; (ii) 188,172 restricted stock units granted on February 6, 2020 which will vest in equal installments on February 6, 2022 and 2023; and (iii) 178,977 restricted stock units granted on February 12, 2021 which will vest in three equal installments on the anniversary of the grant date.

4. Each restricted stock unit represents a contingent right to receive one share of common stock upon vesting of the unit.

5. Restricted Stock Units granted on April 1, 2018 and vesting in three equal installments on the anniversaries of the grant date.

Remarks:

	/s/ Matthew Rinegar, as Attorney-in-Fact	04/02/2021
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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