Exhibit 10.1

AMENDMENT TO ARRANGEMENT AND MERGER AGREEMENT

THIS AGREEMENT made as of the 8th day of May, 2007

AMONG:

VISTA GOLD CORP., a company existing under the laws of the Yukon Territory with
an address at Suite 5 - 7961 Shaffer Parkway, Littleton, Colorado, USA, 80127,

(“Vista”)

AND:

ALLIED NEVADA GOLD CORP., a corporation existing under the laws of Delaware with
an address at 1380 Greg Street, Suite 203, Sparks, Nevada, USA, 89431,

(“Newco”)

AND:

CARL PESCIO, an individual with an address at P.O. Box 5831, Elko, Nevada, USA,
89802,

(“Carl”)

AND:

JANET PESCIO, an individual with an address at P.O. Box 5831, Elko, Nevada, USA,
89802,

(“Janet”, and together with Carl, the “Pescios”)

WITNESSES THAT WHEREAS:

A.                                   Vista, Newco, Carl and Janet are parties to
an arrangement and merger agreement made as of September 22, 2006 (the “Original
Agreement”); and

B.                                     the parties hereto wish to amend the
Original Agreement to add (i) certain additional unpatented mining claims to
Schedule B to the Original Agreement, such additional claims to form part of the
“Vista Nevada Assets” as defined in the Original Agreement and (ii) certain
additional unpatented mining claims to Schedule C to the Original Agreement,
such additional claims to form part of the “Pescio Nevada Assets” as defined in
the Original Agreement;

NOW THEREFORE, in consideration of the mutual agreements and covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledge by all a parties, the parties agree as follows:

1.             Schedule B of the Original Agreement is hereby amended as
follows:

The following claims are added under the heading “Hycroft Resources &
Development, Inc.”:

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Hycroft Mine, Humboldt County, Nevada

Claim Names

 

BLM Serial No. (NMC)

 

Humbolt County Document #

 

 

 

 

 

FG 223 thru FG 226

 

NMC 939256 thru 939259

 

#2006-7900 thru 2006-7903

 

 

 

 

 

FG 270 thru FG 275

 

NMC 939291 thru 939296

 

#2006-7904 thru 2006-7909

 

 

 

 

 

FG 319 thru FG 324

 

NMC 939332 thru 939337

 

#2006-7910 thru 2006-7915

 

 

 

 

 

FG 368 thru FG 377

 

NMC 939373 thru 939382

 

#2006-7916 thru 2006-7925

 

 

 

 

 

FG 421 thru FG 433

 

NMC 939426 thru 939438

 

#2006-7926 thru 2006-7938

 

 

 

 

 

NFG 1 thru NFG 74

 

NMC 939506 thru 939579

 

#2006-7940 thru 2006-8013

 

 

 

 

 

NFG 76 thru NFG 187

 

NMC 939580 thru 939691

 

#2006-8014 thru 2006-8125

 

The following claims are added under the heading “Hycroft Resources &
Development, Inc. — Hycroft Mine, Pershing County, Nevada”:

Claim Names

 

BLM Serial No. (NMC)

 

Pershing County

 

 

 

 

Book

 

Page

 

 

 

 

 

 

 

FG 1 thru FG 82

 

NMC 939059 thru 939140

 

415

 

360 thru 441

 

 

 

 

 

 

 

FG 84 thru FG 116

 

NMC 939141 thru 939173

 

415

 

442 thru 474

 

 

 

 

 

 

 

FG 121 thru FG 127

 

NMC 939174 thru 939180

 

415

 

475 thru 481

 

 

 

 

 

 

 

FG 130 thru FG 162

 

NMC 939181 thru 939213

 

415

 

482 thru 514

 

 

 

 

 

 

 

FG 164 thru FG 167

 

NMC 939214 thru 939217

 

415

 

515 thru 518

 

 

 

 

 

 

 

FG 173 thru FG 202

 

NMC 939218 thru 939247

 

415

 

519 thru 548

 

 

 

 

 

 

 

FG 215 thru FG 222

 

NMC 939248 thru 939255

 

415

 

549 thru 556

 

 

 

 

 

 

 

FG 226 thru FG 249

 

NMC 939259 thru 939282

 

415

 

557 thru 580

 

 

 

 

 

 

 

FG 262 thru FG 269

 

NMC 939283 thru 939290

 

415

 

581 thru 588

 

 

 

 

 

 

 

FG 275 thru FG 302

 

NMC 939296 thru 939323

 

415

 

589 thru 616

 

 

 

 

 

 

 

FG 311 thru FG 318

 

NMC 939323 thru 939331

 

415

 

617 thru 624

 

 

 

 

 

 

 

FG 324 thru FG 351

 

NMC 939337 thru 939364

 

415

 

625 thru 652

 

 

 

 

 

 

 

FG 360 thru FG 366

 

NMC 939365 thru 939371

 

415

 

653 thru 659

 

 

 

 

 

 

 

FG 367

 

NMC 939372

 

415

 

661

 

 

 

 

 

 

 

FG 377

 

NMC 393382

 

415

 

660

 

 

 

 

 

 

 

FG 378 thru FG 420

 

NMC 939383 thru 939425

 

415

 

662 thru 703A

 

 

 

 

 

 

 

FG 433 thru FG 500

 

NMC 939425 thru 939505

 

415

 

704 thru 771

 

 

 

 

 

 

 

WCX 5 thru WCX 10

 

NMC 941257 thru 941262

 

416

 

591 thru 596

 

 

 

 

 

 

 

WCX 34 thru WCX 58

 

NMC 941263 thru 941287

 

416

 

597 thru 621

 

2

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2.             Schedule C of the Original Agreement is hereby amended as
follows:

The following claims are added under the heading “Stargo Property — Nye County —
Claim Names”:

ST 258 - 337

3.                                        The Original Agreement as hereby
amended shall continue in full force and effect and the provisions of the
Original Agreement, as hereby amended, are ratified and confirmed in all
respects.

4.                                        This Agreement and the Original
Agreement shall be read and construed together as if they constituted one
document, provided that if there is any inconsistency between the Original
Agreement and the provisions of this Agreement, the provisions of this Amending
Agreement shall govern.

5.                                        This Agreement may be executed in any
number of original or facsimile counterparts each of which shall be deemed to be
an original, but all of which together shall constitute one and the same
document.

REMAINDER OF PAGE INTENTIONALLY LEFT BLANK

3

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IN WITNESS WHEREOF the parties have executed this Agreement as of the date first
above written.

VISTA GOLD CORP.

 

 

 

By:

/s/ Michael B. Richings

 

 

Authorized Signatory

 

 

ALLIED NEVADA GOLD CORP.

 

 

 

By:

/s/ Scott A. Caldwell

 

 

Authorized Signatory

 

 

SIGNED, SEALED AND DELIVERED by

)

 

Carl Pescio in the presence of:

)

 

 

)

 

Elizabeth Nunez

 

)

/s/ Carl Pescio

 

Name of Witness

)

CARL PESCIO

 

)

 

/s/ Elizabeth Nunez

 

)

 

Signature of Witness

)

 

 

 

 

SIGNED, SEALED AND DELIVERED by

)

 

Janet Pescio in the presence of:

)

 

 

)

 

Elizabeth Nunez

 

)

/s/ Janet Pescio

 

Name of Witness

)

JANET PESCIO

 

)

 

/s/ Elizabeth Nunez

 

)

 

Signature of Witness

)

 

 

4

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