TSX.V:TU
VANCOUVER, May 29, 2012 /PRNewswire/ - Tigris Uranium
Corp. (TSX.V: TU) ("the Company") is pleased to announce that
it has received a resource estimate covering the Company's
Crownpoint and Hosta Butte Project
located in the Grants Uranium District of McKinley County, New Mexico, USA.
The "Crownpoint
and Hosta Butte Uranium Project Mineral Resource Technical Report -
National Instrument 43-101", dated May 14,
2012 calculates indicated mineral resources on the Project
totalling 29.68 million pounds of U3O8 at an
average grade of 0.104% e U3O8 and inferred
mineral resources totalling 6.13 million pounds of
U3O8 at an average grade of 0.110% e
U3O8 as set out in further detail below.
The Company holds a 100% interest in the mineral
estate (excluding hydrocarbons) in approximately 115,000 acres
(46,400 ha) which encompass the Project (save for approximately 140
acres in which the Company holds a 60% interest), subject only to a
3% gross profits royalty on uranium produced, and the reported
resources are located in 3,020 acres (1,22 ha) of this total. The
resource estimates provided herein are being published in place of
previous resource estimates for the Project, released by the
Company in 2010 and retracted by the Company as a result of a
continuous disclosure review by the British Columbia Securities
Commission (see TU News Release 11-08).
|
Million Tons(1) |
Grade e
U3O8 (%) |
Contained
U3O8
(Million Pounds) |
Crownpoint - Indicated(2) |
9,477,000 |
0.102 |
19,205,000 |
Host Butte - Indicated |
4,799,000 |
0.109 |
10,477,000 |
Total Indicated |
14,276,000 |
0.104 |
29,682,000 |
Crownpoint - Inferred(2) |
743,000 |
0.105 |
1,562,000 |
Host Butte - Inferred |
2,046,000 |
0.112 |
4,571,000 |
Total Inferred |
2,789,000 |
0.110 |
6,133,000 |
(1) GT cutoff: Minimum Grade (% eU3O8) x Thickness
(Feet) for Grade > 0.02 % eU3O8
(2) Disclosed tonnage represents the
Company's 100% interest in the s. 19/29 Crownpoint
Property and its 60% interest in s. 24 Crownpoint Property
The resource estimate covers approximately 3,020
acres located in (A) portions of Sections 24, Township 17 North,
Range 13 West (in which the Company holds a 60% interest) and (B)
Sections 19 and 29, Township 17 North, Range 12 West and Sections,
3, 9, and 11, Township 16 North, Range 13 West (in which the
Company holds a 100% interest), New
Mexico Prime Meridian and uses Canadian Institute of Mining,
Metallurgy and Petroleum definitions.
The Report is authored by Douglas L. Beahm, PEng, PGeo, President of BRS
Inc., a registered member of the Society for Mining, Metallurgy and
Exploration and an independent Qualified Person as defined in NI
43-101. Mr. Beahm has reviewed and approved the technical
information in this news release. The Report will be filed on SEDAR
(www.sedar.com) in the next 45 days.
Methodology
The mineral resource estimate was completed using the GT (Grade x
Thickness) Contour Method for each of individual mineralized zones
of the deposit. The Contour Method, also known as the Grade x
Thickness (GT) method, is a well-established approach for
estimating uranium resources and has been in use since the 1950's
in the US. The technique is most useful in estimating tonnage and
average grade of relatively planar bodies where lateral extent of
the mineralized body is much greater than its thickness, as was
observed for detailed review of the data at Crownpoint and Hosta Butte.
For tabular and roll front style deposits the GT
method provides a clear illustration of the distribution of the
thickness and average grade of uranium mineralization. The GT
method is particularly applicable to the Crownpoint and Hosta Butte deposits as it can
be effective in reducing the undue influence of highgrade or thick
intersections as well as the effects of widely spaced, irregularly
spaced, or clustered drill holes. This method also makes it
possible for the geologist to fit the contour pattern to the
geologic interpretation of the deposit.
For each zone within the Crownpoint and Hosta Butte areas of the
project, limits of mineralization were determined by interpretation
of the drill data. Within these limits the GT and T (Grade x
Thickness and Thickness) were contoured. Although an automated
contouring program was used breaklines or limits were established
where appropriate to constrain the estimate. For example drill
holes with GT values several times the average were limited in
their influence by establishing a breakline. By applying a rock
density factor pounds are directly calculated from the GT contour
data and tons are directly calculated from the T contour data.
Grade is then calculated as GT divided by T.
The GT contour method is used as common practice
for Mineral Reserve and Mineral Resource estimates for similar
sandstone-hosted uranium projects ("Estimation of Mineral Resources
and Mineral Reserves", adopted by CIM November 23, 2003, p 51.). It is the opinion of
the author that the GT contour method, when properly constrained by
geologic interpretation, provides an accurate estimation of
contained pounds of uranium.
The current drill hole database consists of:
- Crownpoint Area - 482 drill
holes (of which 93 did not meet minimum cutoff criteria); and
- Hosta Butte Area -135 drill holes (of which 42 did not meet
minimum cutoff criteria).
The uranium quantities and grades are reported
as equivalent U3O8
(eU3O8), as measured by downhole gamma
logging. The industry standard protocol for reporting uranium in
sandstone hosted deposits in the US has been validated for the
Project.
Cutoff Criteria
A cutoff grade of 0.02% U3O8 and a GT of 0.10
were used as the cutoff criteria for the estimation of the total in
situ mineral resource within the Project. The cutoff assumes that
the mining method to be employed will be ISR as is planned for the
adjacent Uranium Resources Inc. Crownpoint project.
Cutoff criteria for mining projects are
determined based upon estimated metal recovery and production costs
as compared to the value of the metal. No current preliminary
economic assessment and/or feasibility study has been completed for
the Project. Thus, calculation of project specific cutoff criteria
is not possible for the Project at this time. However, the
recommended cutoff criteria is supported by published production
costs for the adjacent Crownpoint
project of Uranium Resources Inc. Uranium Resources Inc.'s
projected Crownpoint production
costs are $11.46 per lb
U3O8 direct and $13.46 per lb U3O8 with
G&A (Pelizza and McCarn, 2004). Given that these costs should
reflect the average grade of the deposit, approximately 0.10 %
U3O8, the cost of recovering lower grade
would be proportionately higher. At the minimum cutoff grade of
0.02% U3O8 (one-fifth of the average grade) it would be expected
that the costs would be approximately 5 times greater or
approximately $57 to $67 $/lb which
is roughly a breakeven cost at a selling price of $65/lb.
Data Verification
The great majority of the geophysical logs were completed by Conoco
Minerals using company owned and operated logging units. A limited
number of logs were completed by Geoscience Logging, a commercial
vendor, but they represent less than 5% of the total logs. Conoco
operated Mount Sopris logging units which were very common in the
industry at the time exploration and development was active at the
Project. Mount Sopris is still active in the industry. The author
worked for two separate major uranium producers in the 1970's and
80's who operated Mount Sopris equipment and is very familiar with
their operation and calibration procedures. While at the site the
author met with a former operator of the logging units and
discussed Conoco's general procedures. The procedures included
field calibration check of the equipment prior to the logging of
each hole (documented on the logs); routine calibration of the
units at the Grants, New Mexico
facility operated by the Department of Energy and full calibration
of the units at the more extensive DOE facility in Grand Junction, Colorado whenever major
changes were made to the units (new probes, cabling etc.). K
factors, deadtimes and water correction factors were recorded on
many of the logs and on all of the internal calculation sheets.
To independently verify the historic electronic
database, a sampling of the geophysical logs, including all of the
core holes, was interpolated using the half amplitude method (Dodd,
1967). The results are predictable in that the half amplitude
method more precisely defines the bed boundaries resulting in a
lesser interpolated mineralized thickness than the computer
routines. Both methods typically yield similar grade thickness (GT)
and thus the half amplitude method has a slightly higher grade than
the computer routine.
The results for Crownpoint are that the independent analog
interpretation yielded a total GT within 3% of the computer
database. When the water factor was applied, the results for Hosta
Butte are that the independent analog interpretation yielded a
total GT within 1% of the computer database. It is the author's
conclusion that for Hosta Butte the use of the database should be
adjusted for the appropriate water factor (1.12).
The author concludes that the electronic drill
hole database available for the Project is reliable for the purpose
of estimating mineral resources.
Historic written procedures for core handling
and sample analysis were available with the core data records. In
sum the cores were split through the zones of interest determined
by the geophysical logs and scanning of the cores with a
scintillometer. All of the samples were assayed using either
a Beta Gamma Scaler or an X-ray fluorescence at the mine
site. Quality control of the on-site assay equipment was
provided through an independent laboratory, Hazen Research, which
completed fluorometric analysis of select samples including the
majority of the higher grade samples. Original assay sheets were
available for 32 of the 35 cores holes.
Core samples from the Crownpoint and Hosta Butte areas were donated
to the USGS Core Research Center (CRC) located at the Denver
Federal Center in Lakewood,
Colorado. The author visited the CRC on May 7, 2012 and reviewed the cores and selected
20 samples from core holes geographically distributed within the
Project. The selected samples were assayed at Intermountain
Labs (IML) in Sheridan, Wyoming, a
certified laboratory.
Confirmatory assays were higher grade than the
historic data. The author concludes that while the
confirmatory data would support a positive adjustment in estimated
grade of uranium, use of the historic core assay data is
conservative, reasonable, and reliable for the purposes of
estimating mineral resources for the Project.
A unit weight of 16 cubic feet per ton or 2.439
tons/m3 was assumed for all mineral resource and reserve
calculations. This assumption was based on data from feasibility
studies prepared by previous operators of the Project but was not
independently confirmed other than to review the density data
available from the core drilling. The use of 16 cubic feet per ton
was recommended by the author as a typical value based on his
mining experience with similar sandstone hosted uranium
deposits.
The author reviewed the historic procedures
followed by the previous operator of the project, Conoco Minerals,
including procedures for rotary and core drilling, geophysical
logging and log interpretation, and sampling and assaying. In
addition, the author reviewed and verified the work product that
was developed for the Project including the original geophysical
and lithologic logs, sampling records, and original core assay
records. It is the author's opinion that the procedures, practices,
and analytical equipment utilized and/or employed on the Project
were consistent with the general industry standards and practices
at that time. The author further concludes that the data utilized
in this report is accurate and reliable for the purposes of its use
in the Report.
About Tigris Uranium Corp.
Tigris Uranium Corp. is committed to maximizing shareholder value
and is well positioned with a treasury of approximately
$9 million and a low annual
expenditure rate. Tigris owns 115,000+ acres (46,400 ha) of private
mineral rights, with an indicated resource of 29.7 MM pounds U3O8
and an inferred resource of 6.1 MM pounds U3O8 (Beahm, 2012)
located in New Mexico's Crownpoint
Uranium District, a portion of which is under NRC license, in a new
progressive New Mexico regulatory
and political environment.
Neither TSX Venture Exchange nor its Regulation Services
Provider (as that term is defined in the policies of the TSX
Venture Exchange) accepts responsibility for the adequacy or
accuracy of this release.
This press release contains projections and
forward-looking information that involve various risks and
uncertainties regarding future events. Such forward-looking
information can include without limitation statements based on
current expectations involving a number of risks and uncertainties
and are not guarantees of future performance. There are numerous
risks and uncertainties that could cause actual results and Tigris
Uranium Corp's plans and objectives to differ materially from those
expressed in the forward-looking information. Actual results and
future events could differ materially from those anticipated in
such information. These and all subsequent written and oral
forward-looking information are based on estimates and opinions of
management on the dates they are made and are expressly qualified
in their entirety by this notice. Except as required by law, Tigris
Uranium Corp. assumes no obligation to update forward-looking
information should circumstances or management's estimates or
opinions change.
SOURCE Tigris Uranium Corp.