The document discusses plans to create a high growth, low cost mid-tier silver producer through a combination of US Gold and Minera Andes. Key points include: - The transaction would create a company called McEwen Mining with a pro-forma market cap of $1.4 billion and production of 7.5 million ounces of silver annually growing to 15.8 million ounces. - McEwen Mining would have a strong balance sheet with $122 million in cash and no bank debt, and properties in Nevada, Argentina and Mexico offering growth potential. - The combined company aims to qualify for inclusion in the S&P 500 stock index by 2015.

1. +
Creating a High Growth, Low Cost
Mid-tier Silver Producer
1

2. Forward Looking and Cautionary Statements
This documents contains certain forward-looking statements and information by each of US Gold and
Minera Andes, including “forward looking statements” within the meaning of the Private Securities
Litigation Reform Act of 1995. The forward-looking statements and information express, as at the date of
this press release, US Gold and Minera Andes’ estimates, forecasts, projections, expectations or beliefs
as to future events and results. Forward-looking statements and information are necessarily based upon
a number of estimates and assumptions that, while considered reasonable by management, are
inherently subject to significant business, economic and competitive uncertainties, risks and
contingencies, and there can be no assurance that such statements and information will prove to be
accurate. Therefore, actual results and future events could differ materially from those anticipated in such
statements and information. Risks and uncertainties that could cause results or future events to differ
materially from current expectations expressed or implied by the forward looking statements and
information include, but are not limited to, the completion of a business combination between Minera
Andes and US Gold (including the numerous approvals required in connection with such a business
combination), risks related to business integration as a result of a successful business combination,
factors associated with fluctuations in the market price of precious metals, mining industry risks, risks
associated with foreign operations, risks related to litigation including specifically but not limited to Minera
Andes’ Los Azules property, property title, the state of the capital markets, environmental risks and
hazards, uncertainty as to calculation of mineral resources and reserves and other risks. Readers should
not place undue reliance on forward-looking statements or information. Neither US Gold nor Minera
Andes undertake any obligation to reissue or update forward-looking statements or information as a
result of new information or events after the date hereof except as may be required by law. See (i) US
Gold’s Annual Report on Form 10-K for the fiscal year ended December 31, 2010 and other filings with
the Securities and Exchange Commission, under the caption “Risk Factors”; and, (ii) Minera Andes’
Annual Information Form as filed on SEDAR (www.sedar.com) and form 40F/A filed with the SEC, for the
period ended December 31, 2010, for additional information on risks, uncertainties and other factors
relating to the forward-looking statements and information. All forward looking statements and information
made in this news release are qualified by this cautionary statement.
2

3. LIFE IS FULL OF DISTRACTIONS.
NO MATTER HOW TEMPTING IT
MAY BE TO VEER OFF YOUR
PATH, KEEP YOUR GOALS IN
FOCUS AND KEEP MOVING
FORWARD.
- Gabriel Cid
3

4. Transaction Details
Proposed Corporate Name: McEwen Mining Inc.
Exchange/Ticker: NYSE / TSX : Ticker TBD
Share Exchange Ratio: 1:0.4 Minera to US Gold
Pro-forma Market Cap: US $1.4 Billion
Pro-forma Shares Outstanding: 252.7 Million
Pro-forma Rob McEwen Ownership: 25% ($345 Million)
Pro-forma Balance Sheet: US $122 Million – No Bank Debt
Expected Closing: Late October
4

5. Share Performance When Paying Premiums
5

6. Avg. Share Exchange Ratio
Time (Minera : US Gold)
18 Months 0.32
15 Months 0.32
12 Months 0.32
9 Months 0.36
6 Months 0.36
3 Months 0.35
2 Months 0.35
1 Months 0.36
2 weeks 0.37
1 weeks 0.39
June 13 0.39
6

7. Goldcorp + Wheaton Combination
Premium Paid: 7%
Goldcorp Performance
Day of Announcement $0.01
Goldcorp Performance
170%
12 Months Upon Closing
7

8. Highlights of Combination
• Current Production + Significant Growth
• Low Cost Producer
• Strong Balance Sheet
• Well Positioned Exploration Portfolio
• Increases Management’s Focus
• One Step Closer to S&P 500
8

9. Goal: Qualify for S&P 2015
Requirements
1. US Company ✔
2. Public Float > 50% ✔
3. Liquidity Threshold ✔
4. Sector Representation ✔
5. US Listing ✔
6. Market Cap. > $5 B ✗
7. 4 Qtrs Positive Earnings ✗
9

10. S&P 500: 2 Remaining Hurdles
Today Pro-forma
1. Market Cap. > $5 B $765 MM $1.4 B
Cash Flow
2. 4 Qtrs Positive Earnings No
Begins
* As of Jun 13, 2011
10

11. Diversified in the Americas
* San Jose: includes just MAI 49% interest
11

12. Significant Growth Pipeline
12

13. Production &
Development
13

14. High Growth + Low Cost
Pro-forma Estimates
7.5 MM oz
Growing
Production
Lowering Costs
2.5 MM oz Cash Cost / Silver oz*
(Gold by-product)
-$0.40 -$1.50
2011E 2014E 2011E 2014E
*Cash cost reported on a by-product basis 14

15. Rob McEwen Big Ownership – No Salary!
Increases Management’s Focus
$345 MM
27x
Avg.
$39 MM $31 MM
$5 MM $3 MM $1 MM $0 MM
McEwen First Silvercorp Hecla Coeur Pan Silver
Mining Majestic D’Alene American Standard
* As of Jun 13, 2011
15

16. Creating a Low Cost, High Margin Producer
Cash Cost (By-Product Basis): McEwen Mining vs Peers
Silver
First Standard
Pan $10.95
Majestic
American
$8.25
$7.85
Coeur
$6.50
Hecla
Silvercorp McEwen $1.05
-$7.60 Mining
2011
-$0.40 2014
-$1.50
*Cash cost reported on a by-product basis
** As of March 31, 2011 16

17. Creating the Next Mid-tier Silver Producer
Production Profile: McEwen Mining vs Peers
24.3 MM
16.8 MM
10.6 MM
7.5 MM 8.5 MM
7 MM
5.6 MM
2.5 MM
McEwen Silvercorp First McEwen Silver Hecla Coeur Pan
Mining Majestic Mining Standard American
2011 2014
*Pro-forma production
** As of Dec 31, 2010 17

18. McEwen Mining Market Cap vs Peers
$3.1 B
$2.0 B $2.0 B $2.1 B
$1.7 B
$1.5 B
$1.4 B*
McEwen Silvercorp First Silver Hecla Coeur Pan
Mining Majestic Standard American
*Pro-forma market cap
** As of June 13, 2011 18

19. Pro-forma Resource Estimates
100.3 MM oz
88.7 MM oz
10.3 B lbs
4.1 MM oz
2.9 MM oz
2.2 B lbs
M&I Inferred M&I Inferred Indicated Inferred
Silver Gold Copper
* As of Dec 31, 2010
19

20. Strong Treasury - No Bank Debt
Cash + Silver / Gold Bullion
$122 MM
$100 MM
$22 MM
Pro-forma US Gold Minera Andes
* As of May 31, 2011
20

21. IF LIFE HAS TAUGHT ME
ANYTHING, IT’S THAT WE ARE
CAPABLE OF FAR GREATER
THINGS THAN ONE CAN
POSSIBLY IMAGINE.
- Ari Merkin
21

22. Early Market Reaction to Deal
7.5%
5.3%
Positive!
1.6%
1.4%
0.5%
MJGI Silver Gold MAI UXG
*As of 2:00 pm, June 14, 2011 22

23. El Gallo - Results of Preliminary
Economic Assessment (Feb 2011)
$18.00 Ag $28.50 Ag
$1,000 Au $1,350 Au
Avg / yr Silver Prod. 5 MM oz 5 MM oz
Avg / yr Gold Prod. 50,250 oz 50,250 oz
Silver Cash Cost1 $5.90 $2.45
IRR2 27% 65%
Payback 2.3 yrs 1.0 yrs
NPV (5%)2 $155 MM $520 MM
Capex $150 MM $150 MM
1) Feb 2011 PEA 2) Net of gold by-product 3) Pre-tax 23

24. 24

25. El Gallo: Potential to Expand Production
25

26. 26

27. 27

28. 28

29. El Gallo – Timeline to Production
2011-12: Exploration 15 Drills - $30 Million
2011-12: Mine Permitting
Q4 2011: Feasibility Study/Resource Update
Late 2012:Construction
2014: Production
29

30. Gold Bar – Cortez Trend, Nevada
Preliminary Economic Assessment (Apr 2010)
§ 60,000 oz Au / yr
§ Cash Costs $600 / oz
§ IRR 60%1,2
§ Payback in 3 yrs1
§ Initial Capital $40 MM
§ NPV (6%) $105 MM 1,2
§ M&I Resource: 1 Million oz Gold
1) $1,150 / oz gold price, 2)Pre-tax, 3) April 2010 PEA 30

31. Gold Bar: Pre-Feasibility Study
Expected Sept 2011
Gold
Mineraliza5on
>
0.2
gpt
Pit
Design
($1,200
Gold)
0
100
200
0
300
600
Meters
Feet
31

32. Gold Bar – Timeline to Production
2011-12: Exploration - $5 Million
Sept 2011: Gold Bar Pre-feasibility
2011-13: Mine Permitting
2013: Construction
Late 2014: Production
32

33. 33

34. Nevada - Tonkin - Cortez Trend
34

35. New Veins @ San Jose Mine
Sofia
Vein
10.13
m
@
14.96
g/t
Au,
1,096
g/t
Ag
5.45
m
@
13.54
g/t
Au,
206
g/t
Ag
1.72
m
@
10.94
g/t
Au,
1,255
g/t
Ag
Micaela
Vein
2.45
m
@
8.33
g/t
Au,
1,484
g/t
Ag
1.09
m
@
33.50
g/t
Au,
2,752
g/t
Ag
35

36. Early Stage 100% Owned
Beside Goldcorp’s $3.6B Purchase
36

37. SANTA
CRUZ
EXPLORATION
TARGETS
37

38. Los Azules – Excellent Copper Results
Stepping out: 1.12% copper over
62.5 meters
4 Best Drill Holes:
• 1.08% copper over 145 meters
• 1.01% copper over 216 meters
• 1.05% copper over 236 meters
• 1.04% copper over 168 meters
38

39. Appendix
39

40. San Jose Mine – Argentina (49%)
• Started production in 2007
• 2010 silver + gold production
- Silver 5.3 MM oz
- Gold 84,000 oz
- Silver cash costs -$1.00
• Started production in 2007
• Large 100,000 acre property
remains underexplored
• October 2010, 9 new veins San
Jose
Mine
Tonnes
Ag
Grade
Au
Grade
Ag
(MM
oz) Au
(MM
oz)
(49%)
(MM)(100%)
(g/t)
(g/t)
(100%)
(100%)
announced, significantly P
&
P
1.5
451
6.33
21.3
0.30
extending the mines life M&I
(incl.
P&P)
Inferred
3.1
3.0
475
373
6.80
5.96
46.6
35.8
0.67
0.57
40

41. El Gallo Project – Mexico (100%)
• Located in Sinaloa State, Mexico
• Discovered by US Gold in 2009
• Consists of the El Gallo,
Palmarito, Magistral Deposits
• Forecasted production
- 5 MM oz Silver
- 50,250 oz Gold
- Silver cash cost $2.50 Ag
Grade
Au
Grade
Ag
Au
El
Gallo
Tonnes
(MM)
(g/t)
(g/t)
(MM
oz)
(MM
oz)
• Bankable feasibility Q4 2011 M&I
12.6
77
0.06
31.2
0.02
Inferred
10.0
52
0.03
16.7
0.01
• Commercial production 2014 Ag
Grade
Au
Grade
Ag
Au
Palmarito
Tonnes
(MM)
(g/t)
(g/t)
(MM
oz)
(MM
oz)
M&I
3.7
71
0.14
8.5
0.02
Inferred
1.6
58
0.10
3.0
0.01
Ag
Grade
Au
Grade
Ag
Au
Magistral
Tonnes
(MM)
(g/t)
(g/t)
(MM
oz)
(MM
oz)
M&I
10.4
-­‐
1.50
-­‐
0.50
Inferred
0.2
-­‐
1.14
-­‐
0.01
41

42. Gold Bar Project – Nevada (100%)
• Located in Nevada’s Cortez Trend
• Previous producer
• Forecasted production
- 60,000 oz Gold / yr
- Gold cash cost $600
• Pre-feasibility Q3 2011
• Commercial production late 2014
Tonnes
Ag
Grade
Au
Grade
Ag
(MM
Au
(MM
Gold
Bar
(MM)
(g/t)
(g/t)
oz)
oz)
M&I
33.5
-­‐
0.91
-­‐
0.97
Inferred
1.3
-­‐
0.54
-­‐
0.02
42

43. Los Azules Project – Argentina (100%)
• Advanced-stage porphyry copper
exploration project
• One of the world's largest
undeveloped copper deposits
• PEA Highlights
- NPV $2.8 Billion
- IRR 21%
- 169,000 tonnes Cu / yr
- Capex. $2.9 Billion
• Pre-feasibility underway
Tonnes
Cu
Grade
Au
Grade
Ag
Grade
Cu
(B
Au
Ag
Los
Azules
(MM)
(%)
(g/t)
(g/t)
lbs)
(oz)
(oz)
Indicated
137
0.73
0.07
1.7
2.2
0.3
7.5
Inferred
900
0.52
0.07
1.7
10.3
2.0
49.2
43