Company Web Site: www.rioaltomining.com

(NI) 43-101 reports from projects located in: Peru (PE)

This report is based on NI 43-101 disclosures and fully diluted share counts available on: 2010-01-26. Metrics have been updated with stock price and metal prices in effect at the close of Canadian markets on 2010-03-11.

External Links: Yahoo News and Quotes  |  Yahoo Message Board  |  StockCharts  |  Stockhouse

More External Links: Rio Alto Merger Conference Call Transcript, May 28, 2009  |  Canadian Insider Trading  |  

Rio Alto Mining Limited: Additional Mining Concessions Acquired at La Arena (March 3, 2010 News Release)

Rio Alto is carrying out the technical and development work necessary to bring the La Arena gold oxide project into production by the end of 2010. The Company expects to release the results of an updated NI 43-101 technical report for the La Arena gold oxide project and gold/copper/molybdenum sulphide project before the end of March.

Rio Alto Mining Limited is focused on developing the La Arena Gold Oxide Project by the end of 2010 to become the next company in Peru to bring a gold project into production and to use cash flow from production to further develop its assets in Peru and Mexico.

Rio Alto Fair Market Share Price Estimate updated daily.

Check RIO Lima Quotes (US$)

La Arena S.A. -- site for La Arena registration and community relations

GoldMinerPulse interview with Alex Black, COO and Director, Rio Alto Mining: Developments at the La Arena gold and copper project. (October 14, 2009)

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CAUTION: This report has been prepared assuming that Rio Alto Mining exercises its options to acquire 100% of the La Arena project from IAMGold. Please see Peru .:. La Arena Project .:. Earn-in Agreement & Option Terms for the details on the IAMGold agreement.

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GoldMinerPulse Most Optimistic Resource Estimate Summary (MORE):
Metrics last with prices in effect at the TSX/TSXV close on 2010-03-11

Project	CC	MVpSh	PP%	MI%	I%	Gold	Copper
La Arena Sulphide	PE	$119.96	0	58%	42%	3.39 M oz	1.34 M t
La Arena Oxide	PE	$9.04	0	98%	2%	929.03 K oz
GoldMinerPulse Metrics - Total All Projects by Metal
Metric / Metal						Gold	Copper
Metal Totals						4.31 M oz	1.34 M t
Metal Prices in US$ (from 2010-03-11)						$1,108.90 per oz	$3.36580 per lb
Metal Value per Share (MVpSh) (Shown in US$ and based on fully diluted share count shown below)						$41.99	$87.01
Percentage of Total Metal Value						32.55%	67.45%
PP% | MI% | I%						0 | 65% | 35%	0 | 59% | 41%
GoldMinerPulse Metrics - Total of All Metals and All Projects using prices at TSX/TSXV close on 2010-03-11
Metal Value per Share (MVpSh)						$129.00   US$
Metal Value Leverage (MVL)						220.22
Market Capitalization as % of Metal Value						0.5%
Recent Stock Price						$0.6   C$   (TSX/TSXV close on 2010-03-11. Conversion rate used: 1 Cnd$ = 0.976275 US$ )
Fully Diluted Share Count						113.94 M    ( Fully diluted share count updated to equal to issued shares plus warrants plus options based on data provided on Rio Alto Web Site Share Structure (January 2010) )
PP% | MI% | I%						0 | 61% | 39%
Market Capitalization     per oz of Gold In Ground						$15.47   US$  |   15.84   C$
Gold Eq Oz Estimate						13.25 M oz   ( 4.31 M oz are in ground)
Market Capitalization     per oz of Gold Equilavent						$5.04   US$  |   5.16   C$
Recent London Prices for Metals in Rio Alto Mining Limited (NI) 43-101-Compliant Reserve and/or Resource Estimates
						Gold	Copper
See terms for more about GoldMinerPulse metrics.

Additional Notes:

La Arena Reserves and Resources    -    The (NI) 43-101 report, Table 1.8_2 on p. 15 of 156 shows approximately 2M oz of gold and 1.27B lbs of copper as a probable reserve which are a subset of the indicated mineral resources shown in Table 1.7_1 on p. 13 of 156. Since the inferred resources also include the probable reserves, GoldMinerPulse has only reported the larger indicated resource.

Based on the plans reported around the expected Rio Alto merger, an update (NI) 43-101 is expected during the summer of 2009.

 

GoldMinerPulse Coverage Status:

• GoldMinerPulse coverage of Rio Alto Mining Limited is complete pending a final internal review.

(NI) 43-101 Report:

Title: La Arena Project, Peru Technical Report
Date: 2008-06 (0 pages)

Updates: Reserves and resource figures taken from Peru .:. La Arena Project .:. Resource & Reserves web page viewed January 2010.

Project Location: La Libertad, Peru

Map View: View project on a Google Map.

Most Optimistic Resource Estimates (MORE):

Metal	MVpSh	Contained Metal Quantity	Ore Grade	Ore Quantity
Gold	$8.89	913.72 K oz	0.490 g/t	58.00 M t
Silver	$0.03	167.83 K oz	0.090 g/t	58.00 M t
Estimate notes: See Peru .:. La Arena Project .:. Resource & Reserves. Cuttoff is 0.15g/t Au. This Valuation Report is prepared assuming that Mexican Silver Mines and Rio Alto merge. Mexican Silver Mines exercies its options to aquire 100% of the La Arena project from IAMGold.

Metal	MVpSh	Contained Metal Quantity	Ore Grade	Ore Quantity
Gold	$0.15	15.30 K oz	0.280 g/t	1.70 M t
Silver	$0.00	19.13 K oz	0.350 g/t	1.70 M t
Estimate notes: See notes for Indicated. Cuttoff is 0.15 g/t Au.

(NI) 43-101 Report:

Title: La Arena Project, Peru Technical Report
Date: 2008-06 (0 pages)

Updates: Reserves and resource figures taken from Peru .:. La Arena Project .:. Resource & Reserves web page viewed January 2010.

Project Location: La Libertad, Peru

Most Optimistic Resource Estimates (MORE):

Metal	MVpSh	Contained Metal Quantity	Ore Grade	Ore Quantity
Gold	$18.59	1.91 M oz	0.270 g/t	220.00 M t
Copper	$51.58	792.00 K t	3,600.000 g/t	220.00 M t
Estimate notes: See Peru .:. La Arena Project .:. Resource & Reserves. Cuttoff is 0.1% Cu. This Valuation Report is prepared assuming that Rio Alto Mines exercies its options to aquire 100% of the La Arena project from IAMGold.

Metal	MVpSh	Contained Metal Quantity	Ore Grade	Ore Quantity
Gold	$14.36	1.48 M oz	0.270 g/t	170.00 M t
Copper	$35.43	544.00 K t	3,200.000 g/t	170.00 M t
Estimate notes: See notes for Indicated. Cuttoff is 0.15 g/t Au.