STOCKHOLDERS' EQUITY: (Tables)

12 Months Ended

Dec. 31, 2012

Activity in treasury stock in the years 2012 and 2011 was as follows (in millions):

	2012			2011
Southern Copper common shares
Balance as of January 1,	$	734.1		$	461.0
Purchase of shares	147.3			273.6
Stock dividend distribution	(151.4		)	—
Used for corporate purposes	(0.2		)	(0.5		)
Balance as of December 31,	729.8			734.1

Parent Company (Grupo Mexico) common shares
Balance as of January 1,	163.7			161.7
Other activity, including dividend, interest and currency translation effect	25.3			2.0
Balance as of December 31,	189.0			163.7

Treasury stock balance as of December 31,	$	918.8		$	897.8

Schedule of share repurchase program activity

					Maximum
					Number of Shares
			Average	Cumulative	that May Yet Be
		Total Number	Price	Number of	Purchased Under	Total Cost
Period		of Shares	Paid per	Shares	the Plan	($ in
From	To	Purchased	Share	Purchased	@ $37.86(1)	millions)
2008:
08/11/08	12/31/08	28,510,150	13.49	28,510,150		$	384.7
2009:
01/12/09	09/30/09	4,912,000	14.64	33,422,150		71.9
2010:
05/05/10	10/14/10	15,600	29.69	33,437,750		0.5
2011:
05/01/11	12/31/11	9,034,400	30.29	42,472,150		273.7
2012:
04/10/12	04/23/12	278,486	30.23	42,750,636		8.4
05/30/12	05/31/12	500,000	28.57	43,250,636		14.3
06/01/12	06/30/12	370,000	28.33	43,620,636		10.5
08/01/12	08/31/12	100,000	32.47	43,720,636		3.2
09/01/12	09/30/12	2,763,850	34.71	46,484,486		95.9
10/01/12	10/31/12	430,000	34.83	46,914,486		15.0
		4,442,336	33.17			147.3

Total purchased		46,914,486	18.72		3,220,925	$	878.1

(1) NYSE price at December 31, 2012

Schedule of activity in Directors' Stock Award Plan

The activity of this plan for the years ended December 31, 2012 and 2011 was as follows:

	2012		2011
Total SCC shares reserved for the plan	600,000		600,000

Total shares granted at January 1,	(271,200	)	(256,800	)
Granted in the period	(14,400	)	(14,400	)
Total shares granted at December 31,	(285,600	)	(271,200	)

Remaining shares reserved	314,400		328,800

Deduction from the amount to be paid to the employee in case of voluntary resignation

If the resignation occurs during:	% Deducted
1st year after the grant date	90	%
2nd year after the grant date	80	%
3rd year after the grant date	70	%
4th year after the grant date	60	%
5th year after the grant date	50	%
6th year after the grant date	40	%
7th year after the grant date	20	%

Deduction from the amount to be paid to the employee in case of involuntary termination

If the termination occurs during:	% Deducted
1st year after the grant date	100	%
2nd year after the grant date	95	%
3rd year after the grant date	90	%
4th year after the grant date	80	%
5th year after the grant date	70	%
6th year after the grant date	60	%
7th year after the grant date	50	%

Employee Stock Purchase Plan

Share based compensation plan

Schedule of stock award activity of the Employee Stock Purchase Plan

The following table presents the stock award activity of the Employee Stock Purchase Plan for the years ended December 31, 2012 and 2011:

	Shares		Unit Weighted Average Grant Date Fair Value
Outstanding shares at January 1, 2012	7,270,341		$	1.16
Granted	—		—
Exercised	(220,430	)	1.16
Forfeited	(94,339	)	1.16
Outstanding shares at December 31, 2012	6,955,572		1.16

Outstanding shares at January 1, 2011	10,920,693		$	1.16
Granted	—		—
Exercised	(3,402,855	)	1.16
Forfeited	(247,497	)	1.16
Outstanding shares at December 31, 2011	7,270,341		$	1.16

New Employee Stock Purchase Plan

Share based compensation plan

Schedule of stock award activity of the Employee Stock Purchase Plan

The following table presents the stock award activity of the New Employee Stock Purchase Plan for the years ended December 31, 2012 and 2011:

	Shares		Unit Weighted Average Grant Date Fair Value
Outstanding shares at January 1, 2012	3,807,146		$	2.05
Granted	—		—
Exercised	(772,850	)	2.05
Forfeited	(89,554	)	2.05
Outstanding shares at December 31, 2012	2,944,742		2.05

Outstanding shares at January 1, 2011	3,901,901		$	2.05
Granted	51,923		2.05
Exercised	—		—
Forfeited	(146,678	)	2.05
Outstanding shares at December 31, 2011	3,807,146		$	2.05

- Definition

Tabular disclosure of an entity's treasury stock, including the average cost per share, carrying basis for each class of treasury stock, description of share repurchase program authorized by an entity's board of directors, the number of shares repurchased, the cost of the shares repurchased, the remaining maximum dollar value of shares available for repurchase under the program, the treatment of the purchase price in excess of the current market value, number of shares held for each class of treasury stock, and other information necessary to a fair presentation.

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