Macusani Yellowcake Inc.: Recoveries Average 88.40% from Latest Metallurgical Tests: Financial News

Macusani Yellowcake Inc.: Recoveries Average 88.40% from Latest Metallurgical Tests
Tuesday August 26, 2008 3:39 pm ET

TORONTO, ONTARIO--(MARKET WIRE)--Aug 26, 2008 -- Peter Hooper, President of Macusani stated, "The test material was selected from drill core taken from both the East and West of the 2 km zone and continue to come back with high recoveries."

Macusani Yellowcake Inc. ("Macusani") (CDNX:YEL.V - News) announced today the results of uranium solubility testing in bottle roll tests conducted on samples collected from various areas on the company's Colibri II and III concessions on the Macusani Plateau.

Forty four samples from various depths along diamond boreholes drilled on platforms 1, 2, 3, 4, 5, 11, 14, and 25 were submitted for testing in bottle rolled test in acid conditions. The samples covered various depths (from surface to 64m depth). The samples covered various grades from very low grades (49 ppm U - 0.116 lb U308) to very high grades (1.65% U - 38.2 U308) - see table.

 

----------------------------------------------------------------------------
                                    Depths          U head            Total
Platform      Sample code               (m)     grade (ppm)     recovery (%)
----------------------------------------------------------------------------
                   P1-R01        5.6 - 8.1          145.00            88.89
              --------------------------------------------------------------
                   P1-R02      41.4 - 42.3           66.93            82.37
   1          --------------------------------------------------------------
                   P1-R03      13.4 - 15.1           81.72            87.14
              --------------------------------------------------------------
                   P1-R05      49.5 - 50.8           54.21            70.53
----------------------------------------------------------------------------
                   P2-R01        0.0 - 1.7           95.95            86.93
              --------------------------------------------------------------
                   P2-R02        1.0 - 3.6          142.00            89.13
              --------------------------------------------------------------
   2               P2-R03        8.0 - 9.6           77.83            85.09
              --------------------------------------------------------------
                   P2-R04      23.1 - 26.2           98.33            90.74
              --------------------------------------------------------------
                   P2-R05      31.3 - 31.8          125.00            89.54
----------------------------------------------------------------------------
                   P3-R01        3.5 - 4.7        1,478.00            95.09
              --------------------------------------------------------------
                   P3-R02        2.6 - 5.1           49.60            85.65
              --------------------------------------------------------------
   3               P3-R03      45.6 - 48.2          449.00            87.93
              --------------------------------------------------------------
                   P3-R05        8.0 - 8.8        1,173.00            96.53
              --------------------------------------------------------------
                   P3-R06      32.2 - 33.5           87.90            84.31
----------------------------------------------------------------------------
                   P4-R01       9.0 - 11.0          727.00            92.39
              --------------------------------------------------------------
                   P4-R02      37.6 - 39.7           51.20            81.42
              --------------------------------------------------------------
                   P4-R03      62.8 - 64.6           86.40            91.92
   4          --------------------------------------------------------------
                   P4-R04      23.6 - 24.1           63.90            93.90
              --------------------------------------------------------------
                   P4-R05      31.0 - 32.1        2,195.00            94.21
              --------------------------------------------------------------
                   P4-R06      28.2 - 29.5       16,500.00            94.43
----------------------------------------------------------------------------

The metallurgical tests have been conducted by Ing. Jose Mallqui (MSc) from TECMMINES employed as a consultant by Macusani Yellowcake Inc. through its Peruvian subsidiary Global Gold. The testwork was run at Colibri Refinery's facilities in Lima and the samples were analysed by CIMM Peru. To date 20 samples have been reported and the work continues on the rest of the samples for which partial results are available.

The forty four samples represent a representative selection of various mineralisation styles, type of uranium mineral paragenesis and ore-bearing structures. The conditions of the tests are listed below and are standard for the entire suite of forty four samples:

 

Sample weight (g)                                         400

                                                 100% passing
Granulometry                                         400 mesh

Ratio L/S                                                  10

pH                                                less than 2

Time (hours)                                               10

Inicial acid consumption (g/1000)                       18.75

Acid strength (g/l)                                       1.9

Inicial acid addition (g)                                 7.5

Initial pH                                               7.25

Test date                                          2008/07/02

The metallurgical tests were run in standard conditions lasting 10 hours (600 minutes) of acid leaching with the pH being measured at the beginning and the end of the bottle roll test (after 10 hours) and the consumption of sulfuric acid being calculated.

The results available to date (from platforms 1, 2, 3 and 4 situated on the eastern part of the concession) show exceptional recoveries, ranging between 81% to 96% and with an isolated recovery of 70%.

A typical dissolution kinetic curve of the uranium in the acid solution is presented in the graph below:

To view the graph, please visit the following link: http://media3.marketwire.com/docs/yelgraph1.pdf.

The metallurgical recovery results obtained during these 20 bottle rolled tests available to date are displayed in the table below:

To view the Uranium Recovery graph, please visit the following link: http://media3.marketwire.com/docs/yelgraph2.pdf.

The average metallurgical recovery of samples run to date, after 10 hours of acid leaching in bottle rolled test is 88.40%. Once the metallurgical tests on samples from the rest of the platforms culminates (platforms 5, 11, 14 and 25) several bulk column leach tests will be run, using the results derived from the bottle rolled tests in order to optimize the testing conditions.

The previous experience of comparing bottle roll results with column leach recovery results demonstrate that the column leach tests have higher final recoveries due to increased leaching time and lower acid consumption due to selective uranium leaching.

Further metallurgical results of the various tests will be published by the company during the next months. This set of analyses is part of a larger metallurgical phase study with the final objective of covering with metallurgical testing the entire strike length of the uranium mineralization exposed to date by drilling (in excess of 2 km along strike). To date the uranium recoveries achieved in the studied areas are high to very high.

About Macusani Yellowcake Inc.

Macusani controls over 20,000 hectares (2,000 km2) of mineral properties on the Macusani plateau in Peru.

There are 24,296,285 common shares of Macusani Yellowcake Inc. outstanding, 32,876,260 common shares, fully diluted.

The TSX Venture Exchange does not accept responsibility for the adequacy or accuracy of this release.