U3O8 Corp. Reports Excellent Metallurgical Recoveries of 97% for Uranium, 97% for Phosphate, 79% for Vanadium & Other Metals ...

U3O8 Corp. (TSX VENTURE:UWE), a Canadian-based company focused on exploration
and resource expansion of uranium and associated commodities in South America,
reports exceptional metallurgical test results on the Berlin Project in
Colombia. Recoveries of 97% for uranium, 97% for phosphate and 79% for vanadium
were achieved from initial metallurgical testwork from six tests undertaken on
two different composite samples. Uranium, phosphate and vanadium constitute
approximately two thirds of the in situ value of the mineralized rock at Berlin.



Good recoveries were also achieved on a suite of potential by-products that
contribute to the remaining one third of the in situ rock value including: 96%
for yttrium (a heavy rare earth); 82% for neodymium (a rare earth key in the
making of powerful magnets); 95% for zinc; 64% for nickel; 54% for molybdenum
and 46% for rhenium.


The results were generated from a two-step process consisting of an initial
acidic ferric iron leach followed by a second leach using hydrochloric or
sulphuric acid. Ferric leach is a proven method for the extraction of uranium,
having been used in uranium mines such as Elliot Lake in northern Ontario.
Ferric leach is well suited to treat the Berlin ore as it generates sufficient
sulphuric acid, when mixed with water, to aid neutralization of the carbonate in
the ore. Weak hydrochloric and sulphuric acid solutions at low temperatures were
sufficient to liberate the metals contained in the residue resulting from the
ferric leach process.


"These metallurgical recoveries are outstanding and exceed our expectations.
We've achieved a breakthrough in extracting the diverse mix of commodities in
the Berlin Project," said Dr. Richard Spencer, President and CEO of U3O8 Corp.
"Furthermore, these results are representative of the whole area drilled to date
- sample material having been selected from approximately 25% of the bore holes
completed in the 2010 resource drilling program. In addition, we are continuing
with various beneficiation tests that are showing potential to further reduce
conceptual processing costs. With these excellent recoveries and a maiden
National Instrument 43-101 ("NI 43-101") resource estimate due out shortly, U3O8
Corp. is demonstrating the potentially high value of the Berlin Project."


Table 1 - Summary of Metallurgical Recoveries from the Berlin Project

Summary results from the nine ferric leach tests undertaken on two composite
samples from the Berlin Project are detailed below. There are two steps to each
test: Step 1 involves leaching the ore with ferric iron and only the residue
from Step 1 is acid leached in Step 2. The extraction results reported above
were derived from the six tests in which hydrochloric acid was used in Step 2 of
the process. 


To view Table 1, please visit the following link:
http://media3.marketwire.com/docs/uweTable1.pdf.


Metallurgical Testwork

Results from the initial metallurgical testwork reported in Table 1 are from two
composite samples that were prepared from 18 intercepts of the 73 bore holes
that intersected the mineralized horizon in the recently completed resource
drilling (Figure 1). This represents approximately 25% of the mineralized
intersections and therefore, the metallurgical tests are representative of the
entire area of the Berlin Project that has been drilled to date. Mineralized
core was shipped to Australia where the two samples were prepared and tested by
SGS Lakefield OreTest in Perth - the first composite included core from five
bore holes, and the second from a further 13 bore holes (Figure 1). Individual
core samples were jaw crushed to a grain size of approximately two millimetres
(10 mesh) and this material was blended and then ground to a finer grain size. 


Optimum extraction conditions were determined from nine tests on the two
composite samples. These tests included two leach steps as follows:


Step 1 - Ferric Leach: Whole ore, without being beneficiated, was leached in a
weakly acidic solution of ferric iron at a temperature of 65 degrees C for 48
hours. The ferric iron is a strong oxidizing agent and dissolves a proportion of
the metals and phosphate in the mineralized material. Under the conditions
tested, the ferric leach process generated sufficient sulphuric acid to
neutralize the carbonate in the Berlin ore, leaving a low-carbonate residue.


Step 2 - Acid Wash: The resulting low-carbonate residue was then washed with
weak hydrochloric acid or weak sulphuric acid at a temperature of 40 degrees C
to liberate the contained metals and phosphate. The quantity of metal in
solution was measured to provide the overall recoveries reported in the Table 1
above. 


The leach parameters that were investigated, included grain size, pulp density,
ferric iron concentration and acid-type. 


Grain size:

Uranium at Berlin occurs in very fine-grained uraninite particles that are five
to 10 micrometres in diameter. Fine grinding would typically be necessary to
liberate such fine-grained mineralization from the ore to enable it to react
with the leach reagent. Hence, in addition to the 106 micrometres grain size
typically used in routine leach tests, tests were also carried out on finer
material that had a maximum grain size of 75 micrometres and 38 micrometres.
Results show that grain size does not significantly affect metal recovery and so
fine-grinding, with associated elevated capital and operating costs, is not
necessary in the processing of the Berlin ore. 


Pulp density:

Low pulp densities of 5% and 10% were chosen in order to ensure a high ratio of
reagent liquid to ore in Step 1, creating conditions that are favourable for
effective leaching. As pulp densities rise, leach efficiencies may be expected
to decrease moderately. This effect was tested in the doubling of the pulp
density from 5% to 10% and results show no significant change in recoveries.
This positive result suggests that ferric leach is likely to be efficient at
higher pulp densities approaching those typically used in commercial operations
(40-50%), which would reduce the amount of reagent liquid required and would
lower costs. Further work will be conducted to optimize pulp density. 


Ferric iron concentration:

Ferric iron concentrations of 25 grams per litre ("g/L") and 50g/L were tested
and both concentrations achieved excellent and comparable metal recoveries
(Table 1). These results show that the ore can be leached efficiently at a
relatively low ferric iron concentration which implies lower reagent costs in
the processing of Berlin ore. 


Acid wash:

In Step 2, two types of acid wash were done with mild-strength acid - 10%
sulphuric acid and 10% hydrochloric acid - to release the contained metals into
solution where they are available for extraction. Hydrochloric acid provided
slightly superior results than those from the sulphuric acid wash (Table1). 


Temperature and nature of reagents and products:

The tests were undertaken at temperatures of 65 degrees C in Step 1 and 40
degrees C in Step 2. These relatively low temperatures should be cost-effective
to achieve at a commercial scale. All tests were conducted at atmospheric
pressure and no noxious gases or fumes were generated. The ferric reagent is
also safe to handle, representing no hazard to personnel. The 10% hydrochloric
acid is the same concentration of acid used in the control of pH in swimming
pools.


Ferric Leach - How It Works:

Metals can be extracted from many uranium ores with acid. This process is
effective on Berlin ore, but acid consumption is very high due to the presence
of carbonates and phosphates. One of the most significant features of the ferric
leach tests undertaken on the Berlin ore is that no acid was added to control pH
in Step 1 of the leach process. This is because ferric sulphate reacts naturally
with water to generate jarosite and sulphuric acid, as acid demand increases.
This can be represented as follows:
http://media3.marketwire.com/docs/uweformula12.pdf.


Ferric Consumption: 

Ferric iron may be generated on-site from pyrite, which provides a potentially
low-cost, local source of the reagent. Ferric iron consumption is estimated to
be approximately 100 kilograms ("kg") per tonne of ore based on 50g/L of ferric
iron concentration. Making relevant assumptions for the cost of power, an
in-house cost estimate for on-site ferric reagent supplemented with external
fresh sulphuric acid is approximately $60 to $95 per tonne of ore, assuming that
the acid demand for the ore remains high. In this scenario, approximately 140kg
of fresh sulphuric acid per tonne of ore would be required to supplement the
ferric reagent, which is included in the cost estimate. These values require
verification in an independent scoping study, but provide a positive incentive
to develop a process flow sheet focused on the use of ferric leaching. Clearly,
if the beneficiation tests that are underway on the ore are successful in
separating acid-consuming calcite from the material that undergoes ferric leach,
acid consumption would be reduced, resulting in decreased ferric iron demand and
external acid requirements, which would lower reagent costs. 


Additional Metallurgical Testwork

Having established the ferric leach method as a viable approach, SGS Lakefield
OreTest is conducting further test work with the aim of refining the various
parameters to optimize estimated processing costs and recoveries of the
different elements and define efficiencies towards developing a process flow
sheet. 


In addition to the ongoing test work at SGS OreTest, beneficiation tests are
being carried out on samples from Berlin with results to be reported as they
become available. These include:




--  Organic acid leach - SGS Lakefield in Ontario is conducting leach tests
    with organic acid (vinegar) as a means of consuming calcite without
    dissolving phosphate. Successful reduction of the calcite content of the
    ore should lower reagent consumption with associated reduction in
    operating costs; and 
--  Flotation - Optimet in Australia is conducting tests to determine
    whether calcite can be separated from the phosphate by various flotation
    methods. 



Qualified Persons and Accreditation

The metallurgical testwork reported on above was done at SGS Lakefield OreTest
Pty Ltd in Perth, Australia. SGS Lakefield OreTest was established as a
metallurgical services company in 1993 as Lakefield OreTest Pty Limited and is
now a subsidiary of the SGS Lakefield group, which has been offering mineral
processing services to the mining industry since 1948.


Dr. Paul Miller, a Qualified Person within the definition of that term in NI
43-101 of the Canadian Securities Administrators, has overseen the metallurgical
test work carried out by SGS Lakefield OreTest, and verified the technical
information relating to the tests from which results are reported in this press
release. Dr. Miller is a metallurgist who has specialized in hydrometallurgy and
has over 30 years' experience in the commercial application of processes for the
treatment of sulphide-bearing ore. Dr. Miller has a doctorate in Chemical
Engineering, is a member of the Institute of Mining and Metallurgy, London, and
is also a Chartered Engineer. He is currently Managing Director of Sulphide
Resource Processing Pty Ltd.


Dr. Richard Spencer, P. Geo., President & CEO of U3O8 Corp., a Qualified Person
within the definition of that term in NI 43-101 of the Canadian Securities
Administrators, has supervised the preparation of, and verified the technical
information relating to the Berlin Project provided above. 


About U3O8 Corp. 

U3O8 Corp. is a Toronto-based exploration company focused on exploration and
resource expansion of uranium and associated commodities in South America - a
promising new frontier for exploration and development. U3O8 Corp. has one of
the most advanced portfolios of uranium projects in the region comprising NI
43-101 compliant resources in Guyana and Argentina to significant historic
resources in Colombia.


For further information on U3O8 Corp's Berlin Project, refer to the technical
report entitled "Review of Historic Exploration Data from the Uraniferous Black
Shales of the Berlin Project and Chaparral Concession, Colombia: A guide to
future exploration" prepared by Richard Spencer and Richard Cleath dated March
23, 2010 and available at www.sedar.com. Additional information on U3O8 Corp. is
available on the company's web site at www.u3o8corp.com. 


Forward-Looking Statements

Certain information set forth in this news release may contain forward-looking
statements that involve substantial known and unknown risks and uncertainties.
These forward-looking statements are subject to numerous risks and
uncertainties, certain of which are beyond the control of U3O8 Corp., including,
but not limited to, the impact of general economic conditions, industry
conditions, the timing of laboratory results and preparation of technical
reports, the actual results of independent scoping studies and subsequent
metallurgical testing, volatility of commodity prices, risks associated with the
uncertainty of exploration results and estimates and that the resource potential
will be achieved on exploration projects, currency fluctuations, dependence upon
regulatory approvals, and the uncertainty of obtaining additional financing and
exploration risk. There is no assurance that the Berlin Project will add to U3O8
Corp's resource base in the short-term, or at all. Readers are cautioned that
the assumptions used in the preparation of such information, although considered
reasonable at the time of preparation, may prove to be imprecise and, as such,
undue reliance should not be placed on forward-looking statements. 


To view Figure 1 - Map of the "Unfolded" Mineralized Layer in the Southern Part
of the Berlin Project, please visit the following link:
http://media3.marketwire.com/docs/u308Fig1.pdf.


This map depicts the mineralized layer in the southern part of the Berlin
Project "unfolded" into a flat sheet. Each coloured circle marks the pierce
point at which a bore hole intersected the mineralized sheet from which samples
were used in the metallurgical testing reported in this press release. 


To view the first photo associated with this release, please visit the following
link: http://media3.marketwire.com/docs/uwebproject12.JPG.


To view the second photo associated with this release, please visit the
following link: http://media3.marketwire.com/docs/uwebdrill12.JPG.