Norsemont Mining Inc.
OTC Bulletin Board : NOMFF

Norsemont Mining Inc.

April 05, 2007 09:01 ET

Norsemont Reports Over 87% Copper Recoveries From Initial Metallurgical Testing at the Constancia Project

VANCOUVER, BRITISH COLUMBIA--(CCNMatthews - April 5, 2007) - Norsemont Mining Inc. ("Norsemont" or "the Company") (TSX:NOM)(OTCBB:NOMFF)(FRANKFURT:N8S)(WKN:A0DQKK)(ISIN:CA6565291045) is pleased to report that C.H. Plenge Laboratories, under the supervision of Transmin Metallurgical Consultants, have completed the first pass program of laboratory flotation testing on Constancia drill core samples. The work, done in preparation for a project scoping study later in 2007, has been very successful with the mineralogy and locked cycle flotation test results showing that the copper values essentially occur as coarse liberated primary and secondary copper sulphides that can be readily recovered to a commercial concentrate by standard flotation. Three stages of cleaning were used in the locked cycle tests. Overall copper recovery is indicated to be in the range 87 - 89%.

"We are pleased with the excellent recoveries and concentrate grades from this initial round of testing at the Constancia Project. Further testing work will allow us to optimise these results with a more comprehensive suite of metallurgical testwork throughout the deposit," said Robert Baxter, President, Norsemont Mining Inc.

Three master composites were produced from drill core samples as part of an initial flowsheet and design criteria development program. Preliminary results indicate that the process flowsheet for Constancia will be a conventional copper-molybdenum porphyry flowsheet, with a grind size of 106 to 150 micrometers followed by copper-molybdenum rougher flotation, concentrate regrind to 20 to 37 micrometers and three stages of copper cleaner flotation. A separate molybdenum concentrate would likely be separated from the bulk copper molybdenum concentrate by employing standard technology used industrially for similar deposits.

Three composite samples were made up of drill core from the 2006 drilling campaign. Supergene (SG), hypogene (HG) and skarn (SK) samples were composited from several drill holes based on location, grade lithology and alteration.

The average metallurgical results are summarized in the Table below from the locked cycle tests.

A limited amount of sample was available for this first round of testwork and therefore optimization testwork has yet to be completed. There remains substantial opportunity to improve metallurgical performance through further optimization testwork. Fresh drill core samples have been delivered to Plenge in Lima for the next round of testwork that will be used to complete metallurgical testwork to the Pre-Feasibility Study (PFS) level.

This work will include:

- Molybdenum recovery

- Zinc recovery

- Grind Vs Recovery optimization

- Crushing and grinding work indices

- Copper recovery optimization

- Copper concentrate cleaning optimization

The composite characteristics are as follows;

Element HY SG SK

Ag g/t 3.6 3.2 4.6
Au g/t 0.045 0.028 0.105
Cu total % 0.54 1.09 0.58
Cu H2SO4 % 0.08 0.16 0.05
Cu CN- % 0.10 0.74 0.04
Cu residual % 0.33 0.13 0.46
Mo % 0.034 0.015 0.005
Fe % 1.62 2.73 8.31
S total % 1.22 2.33 3.89
S sulfur % 0.95 1.90 2.87
C % 0.14 0.10 2.76
Pb % 0.05 0.03 0.06
Zn % 0.07 0.03 0.28
Hg ppm 0.6 0.1 0.3

Sp- G g/cc 2.66 2.69 2.89

Natural pH 6.9 5.8 7.8

Highlights of First Phase Locked Cycle Test Results are as follows:

Concentrate Assays Recovery %
Sample Wt Ag Au Cu Mo Fe S
No. % g/t g/t % % % % Ag Au Cu Mo
HY 1.51 186 0.55 29.6 0.68 27.7 30.2 78.2 18.5 89.4 35.2
SG 2.81 101 0.34 31.4 0.21 26.1 33.1 88.5 33.5 87.3 52.0
SK 1.76 135 1.64 26.6 0.03 25.3 28.9 51.6 27.5 88.2 14.1

The grade of the skarn copper concentrate has been diluted by the presence of zinc in the final concentrate. The next round of testwork will include stronger zinc depression in the copper cleaning circuit to improve the grade of the copper concentrate and activation of the zinc in the copper tails to produce a zinc concentrate.

Adam Johnston (MAusIMM) of Transmin Metallurgical Consultants is the company's qualified person on metallurgical aspects of this press release.

On March 28 the company released an independent Mineral Resource estimate on the Constancia and San Jose Zones of the Constancia Deposit in Southern Peru by Snowden Mining Industry Consultants Inc. ("Snowden"). The report estimates an Indicated Resource of 70.0 million tonnes grading 0.53% copper, 0.013% molybdenum and 4.0 g/t silver (0.65% Cu-Equivalent) at a cutoff grade of 0.2% copper and an Inferred Resource of 250.2 million tonnes grading 0.51% copper, 0.013% molybdenum and 4.5 g/t silver (0.64% Cu-Equivalent) at a cutoff grade of 0.2% copper.

About Norsemont Mining

Norsemont Mining is a well structured, well financed exploration company working in the America's, with a focus on Peru. The Company is currently drilling the Constancia Copper-Molybdenum-Silver Deposit, joint ventured from Rio Tinto.


Robert W. Baxter, President

Norsemont Mining Inc.

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