Denison Mines Corp.
TSX : DML

Denison Mines Corp.

February 23, 2007 09:29 ET

Denison Reports More High-Grade Uranium Results at Moore Lake

TORONTO, ONTARIO--(CCNMatthews - Feb. 23, 2007) - Denison Mines Corp. ("Denison") (TSX:DML) and JNR Resources Inc. ("JNR") (TSX VENTURE:JNN), jointly the "Companies", are pleased to announce the results from the 2006 summer/fall diamond drilling program on the Moore Lake uranium project located in the Athabasca Basin of northern Saskatchewan. The program consisted of 38 holes totalling 14,317 metres. The Moore Lake project is a joint venture between the two companies, with participating interests of 25% (JNR) and 75% (Denison).

Summary of Results

The Companies are pleased with the results, which continue to outline uranium mineralization in the Maverick Main zone and demonstrate the highly prospective nature of the 6.5-kilometre long Maverick structural corridor, over 50% of which has yet to be drill tested, and the Avalon conductive zone. Significant results are presented in the table below.

Infill drilling on the Maverick Main zone intersected uranium mineralization in all six holes, with high-grade intersections in three of them. ML-140 returned 3.20% U3O8 over 6.5 metres including a 3.5-metre intercept of 5.25% U3O8, 2.1% nickel and 0.65% cobalt. ML-139 returned 1.23% U3O8 over 8.5 metres, including a 1.5-metre intercept of 4.20% U3O8. The mineralization in both of these holes occurs at the unconformity and in the basal sandstone. Also at the Maverick Main zone, ML-133 intersected two zones of mineralization. A high-grade zone at the unconformity returned 2.72% U3O8, 2.30% nickel and 0.905% cobalt over 5.0 metres, including a 2.0-metre intercept of 4.25% U3O8. ML-133 also intersected mineralization in the basement associated with clay-altered graphitic pelites, returning 0.611% U3O8 over 3.5 metres.

Uranium mineralization was intersected in all three holes that tested the '527' area, with the best result obtained from ML-136 returning 0.50% eU3O8 over 7.0 metres.

Significant results were obtained from several holes that tested the minimum 4.0 kilometre long conductive zone on the Avalon grid. Of particular interest was ML-850, which represents the first-pass drilling of a 1.0 kilometre segment of the zone. It intersected a broad 25-metre zone of highly anomalous radioactivity located well beneath the unconformity.

Extensive structural disruption and/or anomalous geochemistry were intersected in the majority of holes that tested other target areas (further details of the results from the various grids are presented below). A full evaluation of all of these zones will be undertaken, and follow up drilling is planned on a number of highly prospective targets.

The 2007 winter exploration program is well underway. It will consist of a planned minimum of 10,000 metres of diamond drilling and 110 kilometres of linecutting and ground geophysics. A property-wide airborne resistivity and magnetic survey will also be carried out. Two drills are currently operating, and in light of the substantial freeze this winter, they will focus on muskeg and lake covered targets in the West Venice, Venice, Volhoffer, Puka Puka and West Maverick areas. The Companies have budgeted a total of $5.0 million for exploration in 2007.

It should be noted that depths to the unconformity along the Maverick structural corridor are relatively shallow at 270 to 275 metres. In the Avalon area they are on the order of 320 to 330 metres. The shallowest unconformity depths on the property (approximately 200 metres) are on the Rarotonga grid.



Moore Lake Drilling
Summer/Fall 2006 Program
Significant Results

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Grid Hole # From To Interval % % % %
(m) (m) (m) eU3O8 U3O8 Ni Co
-------------------------------------------------------------------
Maverick
Main ML-133 266.0 271.0 5.0 2.72 2.3 0.905
269.0 271.0 2.0 4.25
280.0 283.5 3.5 0.611

ML-135 263.5 267.5 4.0 0.822 1.37 0.68
263.5 265.0 1.5 1.3
273.0 275.5 2.5 0.217
273.0 273.5 0.5 0.625

ML-137 273.0 275.0 2.0 0.086

ML-139 264.5 273.0 8.5 1.23

ML-139 270.0 271.5 1.5 4.2

ML-140 262.9 269.4 6.5 3.2
265.4 268.9 3.5 5.25 2.1 0.65

ML-141 278.5 280.0 1.5 0.671
-------------------------------------------------------------------
527'
Zone ML-132 277.5 279.7 2.2 0.156
284.1 286.4 2.3 0.37

ML-134 283.5 288.0 4.5 0.106
284.5 285.0 0.5 0.551

ML-136 275.1 282.1 7.0 0.5
-------------------------------------------------------------------
Maverick
NE ML-124 281.75 286.4 4.65 0.033
291.5 292.0 0.5 0.411

ML-128 288.0 290.5 2.5 0.109
-------------------------------------------------------------------
Avalon ML-850 351.0 354.0 3.0 0.088
371.0 371.5 0.5 0.057
380.5 383.0 2.5 0.059
-------------------------------------------------------------------



-----------------------------------------------------------
Grid Hole # Dip UTM E UTM N Elev. U/C Hole
(m) Depth Depth
(m) (m)
-----------------------------------------------------------
Maverick
Main ML-133 -90 491943 6363730 503.0 268.1 353.0


ML-135 -90 491952 6363731 503.0 269.9 347.0



ML-137 -90 491962 6363734 503.0 270.1 347.0

ML-139 -90 491992 6363747 503.0 272.7 372.0

ML-139

ML-140 -90 491977 6363743 502.0 267.1 349.1

ML-141 -90 491945 6363731 503.0 269.3 351.0
-----------------------------------------------------------
527'
Zone ML-132 -90 492436 6363949 510.0 278.0 325.3

ML-134 -90 492416 6363934 510.0 279.2 329.0

ML-136 -90 492434 6363954 510.0 275.3 326.0
-----------------------------------------------------------
Maverick
NE ML-124 -90 492604 6364032 512.0 281.5 339.5

ML-128 -90 492520 6363982 512.0 284.0 358.0
-----------------------------------------------------------
Avalon ML-850 -90 495851 6371093 500.0 313.6 431.0


-----------------------------------------------------------


Full Description 2006 Summer/Fall Drill Program

Maverick Main Zone

Six holes were drilled to complete sections and to fill in gaps on the Main lens of the Maverick zone. All six holes intersected uranium mineralization with high-grade in three of them.

ML-140 returned 3.20% U3O8 over 6.5 metres, including a 3.5 metre intercept of 5.25% U3O8, 2.1% nickel and 0.65% cobalt. ML-139 returned 1.23% U3O8, over 8.5 metres, including a 1.5 metre intercept of 4.20% U3O8. The mineralization in both of these holes occurs at the unconformity and in the basal sandstone.

ML-133 intersected two zones of mineralization. A high-grade zone at the unconformity returned 2.72% U3O8, 2.30% nickel and 0.905% cobalt over 5.0 metres, including a 2.0-metre intercept of 4.25% U3O8. ML-133 also intersected mineralization in the basement associated with clay-altered graphitic pelites, returning 0.611% U3O8 over 3.5 metres.

ML-135 intersected two zones of mineralization. A 4.0-metre interval in the basal sandstone assayed 0.822% U3O8, 1.37% nickel and 0.68% cobalt, including a 1.5-metre intercept of 1.30% U3O8. A 2.5-metre interval associated with graphitic pelites just below the unconformity assayed 0.217% U3O8 over 2.5 metres, including a 0.5-metre intercept of 0.625% U3O8.

Although ML-141 and -137 both deviated to the south of their intended pierce points, they did intersect narrow zones of mineralization within basement graphitic pelites. ML-141 returned 0.671% U3O8 over 1.5 metres while ML-137 returned 0.086% U3O8 over 2.0 metres.

'527' Zone

Time constraints allowed for the drilling of only three holes on the '527' zone. ML-136 and -132 were drilled on section, testing for a northeast extension to the mineralization intersected in discovery holes ML-527 and -101.

The better results were from the northernmost hole, ML-136, which returned 0.50% eU3O8 over 7.0 metres. This intersection occurred in the basal sandstone and underlying graphitic pelites. ML-132 intersected two low-grade zones of mineralization. A 2.2-metre intercept straddling the unconformity returned 0.156% eU3O8, while a 2.3-metre intercept within the basement graphitic pelites returned 0.37% eU3O8.

ML-134, which tested for a southwest extension to the mineralization intersected in ML-527 and -101, returned 4.5 metres of 0.106% U3O8 associated with clay-altered graphitic pelites. This included a 0.5-metre interval of 0.551% U3O8.

Maverick Northeast

Nine holes were drilled in this area as part of the ongoing systematic testing of the Maverick structural corridor and follow-up to previously completed holes.

ML-138 and -128 were drilled on section and 100 metres to the northeast of the '527' zone. Both holes were drilled in the hanging wall and intersected a structurally disrupted and strongly altered basal sandstone column, overlying clay-altered and sheared basement containing multiple zones of graphitic pelites. These graphitic rocks exhibit anomalous radioactivity and returned significant enrichment in all of the pathfinder elements. The best result was from a 2.5-metre interval in ML-128 that returned 0.109% U3O8. ML-127 which was collared a further 50 metres to the northeast was also a hanging wall hole and was geologically and geochemically analogous to ML-138 and -128.

ML-131 and -124 were drilled 50 metres to the northeast of ML-127 and on section with ML-40. ML-124 was drilled in the hanging wall and intersected a strongly altered basal sandstone column. The initial several metres of basement rocks are anomalously radioactive and locally metal-enriched, clay-altered granites, followed by sheared graphitic pelites. A 0.5-metre interval from the latter returned 0.411% U3O8. ML-131 intersected a strongly altered basal sandstone column and hematized granitic basement rocks.

ML-125 and -126 were progressive 50-metre step outs to the northeast of section ML-131, -124, -40. Both holes intersected on the hanging wall side of the target in a strongly altered basal sandstone column. The initial 60 to 70 metres of basement consisted of strongly clay-altered and structurally disrupted granites and graphitic pelites, commonly enriched in the key pathfinder elements.

ML-130 and -129 were drilled on section with, and north and south, of ML-512 and -75 respectively. Although both holes were geologically and geochemically anomalous, neither intersected significant uranium mineralization.

Esker

The Esker grid covers an interpreted north-northwest trending shear zone that occurs at the northeast end of the currently known limits of the Maverick structural corridor, some 3.0 kilometres to the northeast of the Maverick Main lens. Prior drilling in this area by previous operators intersected geochemically anomalous and structurally disrupted sandstone and basement rocks in a number of holes, as well as pitchblende mineralization (3070 ppm U/0.25 m) accompanied by significant metal enrichment in the basement of MT-5. Three holes were drilled during the recent program, all of which met with encouraging results.

ML-535 was lost in a major sandstone structure at 206 metres. The entire sandstone column was strongly altered and structurally disrupted.

ML-536 was drilled in the hanging wall. It intersected a strongly altered basal sandstone column with weak uranium enrichment. The basement rocks are largely orthogneiss and locally enriched in uranium (up to 140 ppm/0.5 m). Of note is a 45-metre wide graphitic unit that was intersected some 90 metres below the unconformity.

ML-537 was also a hanging wall hole that intersected strong uranium enrichment and illite alteration in the basal 50 metres of the sandstone column. This hole intersected a 35-metre wide sheared graphitic pelite beginning some 20 metres into the basement, which was also enriched in some of the key pathfinder elements.

West Maverick

Five holes (ML-118 to -121 and -534) were drilled on section with ML-05 and -10, some 250 metres to the west of the Maverick Main lens. They were drilled at 10-metre step outs to test for both western and northwestern extensions to the mineralizing and conductive system, and to provide geological information in this crucial area.

All five intersected a structurally disrupted and strongly altered sandstone column that was geochemically highly anomalous. Uranium and boron values are commonly well above background and the clay type is a mix of illite and dravite. The anomalous system, particularly with respect to uranium, increases in intensity to the south suggesting a possible source in this direction. The sandstone column in the southernmost hole, ML-534, contains up to 7.5 ppm uranium.

The basement rocks in these holes are also altered and commonly structurally disrupted. They contain multiple graphitic horizons that are enriched in uranium and a number of key pathfinder elements including; nickel, cobalt, vanadium, boron, copper, lead and bismuth.

Avalon

Eight holes were drilled in this area testing a minimum 4.0-kilometre long, north-northeast trending conductive zone that is transected by an east-west structural corridor in its central portion. These holes represented both a first-pass test of large segments of the target and follow-up to encouraging results from previous drilling.

The most encouraging results were from ML-850 and -853, which were drilled on section and collared on a 1.0-kilometre long, previously untested segment of the conductive zone. ML-850 intersected a broad zone of highly anomalous radioactivity associated with altered and sheared graphitic pelites that occur from 35 to 60 metres below the unconformity. Individual mineralized zones assayed 0.088% U3O8 over 3.0 metres, 0.057% U3O8 over 0.5 metres and 0.059% U3O8 over 2.5 metres. A number of additional samples returned on the order of 100 to 300 ppm uranium over 0.5 metres. Associated with this mineralization is a significant enrichment in all of the major pathfinder elements. Also of note is that pegmatites intersected below the mineralized graphitic pelites are also enriched in uranium (up to 250 ppm/0.5m).

ML-853 intersected a 20-metre wide zone of anomalous radioactivity beginning some 35 metres below the unconformity, and a 15-metre wide zone beginning some 75 metres into the basement. Both are associated with brittlely-fractured and altered pegmatites. The upper zone returned up to 375 ppm uranium over 0.5 metres, while the lower zone returned up to 105 ppm uranium over 0.5 metres.

ML-852 was collared 600 metres to the south of section ML-853 and -850. It was drilled in the hanging wall and intersected an illitic basal sandstone column enriched in lead and graphitic pelites in the basement , returning anomalous vanadium, nickel and zinc values and up to 150 ppm uranium over 0.5 metres. ML-851, which was collared a further 400 metres to the south and on section with ML-709, intersected basement graphitic pelites that returned anomalous copper and lead values and up to 130 ppm uranium over 0.5 metres. Radioactive pegmatites that were intersected beneath the pelitic rocks returned up to 350 ppm uranium over 0.5 metres.

ML-846 to -849 were follow-up holes drilled in the central portion of the conductive zone. ML-846, -847 and -849 all exhibited similar geological and geochemical characteristics; a strongly altered and commonly illitic basal sandstone column enriched in uranium, and a basement that contains altered and sheared graphitic pelites locally enriched in uranium and pathfinder elements such as cobalt, nickel, vanadium and boron. ML-848 intersected a strongly altered and illitic basal sandstone column overlying a largely altered and sheared granitic basement. A 2.5-metre section of this unit is enriched in uranium (up to 100 ppm/0.5 m), vanadium, boron and lead.

Miscellaneous

ML-122 and -123 tested interpreted seismic structures on the West Maverick and Maverick grids, respectively. Both intersected well-defined basement structures but no significant mineralization. ML-123 did intersect altered graphitic pelites some 65 metres below the unconformity that were enriched in boron, vanadium and nickel.

ML-844 and -845 tested conductive targets in the Nutana and West Venice areas respectively. Both were drilled in the hanging wall, intersecting fractured and altered graphitic pelites enriched in uranium (up to 150 ppm), nickel, copper and vanadium, well below the unconformity.

For a description of the quality assurance program and the quality control measures applied by JNR during the above described work, please see the Material Change Report filed on December 2, 2004 by JNR on the SEDAR website at www.sedar.com. Details of the QAQC program may also be viewed on JNR's website at: www.jnrresources.com/i/pdf/JNR-QAQC.pdf. A glossary of the technical terms included in this release can be found on JNR's website at: www.jnrresources.com/s/Glossary.asp.

Paul Ogryzlo, P.Geo., a Qualified Person pursuant to NI 43-101, has reviewed the contents and technical information contained in this news release. Mr. Ogryzlo is Director, Exploration for Denison. Samples were analysed at the Saskatchewan Research Council Laboratory in Saskatoon.

Denison Mines Corp. is the premier intermediate uranium producer in North America, with mining assets in the Athabasca Basin Region of Saskatchewan, Canada and the southwest United States including Colorado, Utah, and Arizona. Further, the Company has ownership interests in two of the four uranium mills operating in North America today. The combination of a diversified mining asset base with parallel ownership of milling infrastructure in highly politically stable jurisdictions has uniquely positioned the Company for growth and development into the future. The Company also has a strong exploration portfolio with large land positions in the United States, Canada and Mongolia. Correspondingly, the Company has one of the largest uranium exploration teams among intermediate uranium companies.

Cautionary Statements

This news release contains "forward-looking statements", within the meaning of the United States Private Securities Litigation Reform Act of 1995 and similar Canadian legislation, concerning the business, operations and financial performance and condition of Denison Mines Corp. ("Denison").

Forward looking statements include, but are not limited to, statements with respect to estimated production, synergies and financial impact of the proposed transaction; the benefits of the proposed transaction and the development potential of Denison's properties; the future price of uranium; the estimation of mineral reserves and resources; the realization of mineral reserve estimates; the timing and amount of estimated future production; costs of production; capital expenditures; success of exploration activities; permitting time lines and permitting, mining or processing issues; currency exchange rate fluctuations; government regulation of mining operations; environmental risks; unanticipated reclamation expenses; title disputes or claims; and limitations on insurance coverage. Generally, these forward-looking statements can be identified by the use of forward-looking terminology such as "plans", "expects" or "does not expect", "is expected", "budget", "scheduled", "estimates", forecasts", "intends", "anticipates" or "does not anticipate", or "believes", or variations of such words and phrases or state that certain actions, events or results "may", "could", "would", "might" or "will be taken", "occur" or "be achieved".

Forward looking statements are based on the opinions and estimates of management as of the date such statements are made, and they are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of Denison to be materially different from those expressed or implied by such forward-looking statements, including but not limited to risks related to: unexpected events during construction, expansion and start-up; variations in ore grade, tonnes mined, crushed or milled; delay or failure to receive board or government approvals; timing and availability of external financing on acceptable terms; risks related to international operations; actual results of current exploration activities; actual results of current reclamation activities; conclusions of economic evaluations; changes in project parameters as plans continue to be refined; future prices of uranium and vanadium; possible variations in ore reserves, grade or recovery rates; failure of plant, equipment or processes to operate as anticipated; accidents, labour disputes and other risks of the mining industry; delays in the completion of development or construction activities, as well as those factors discussed in or referred to in the current annual Management's Discussion and Analysis of each of Denison Mines Inc. ("DMI") and International Uranium Corporation ("IUC"), the current Annual Information Form of DMI filed with the securities regulatory authorities in Canada and available at www.sedar.com and IUC's Annual Report on Form 20-F filed with the securities regulatory authorities in Canada and available at www.sedar.com. Although management of Denison has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended.

There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Denison does not undertake to update any forward-looking statements that are incorporated by reference herein, except in accordance with applicable securities laws. Mineral resources, which are not mineral reserves, do not have demonstrated economic viability. Readers should refer to the respective Annual Information Forms of DMI and, IUC, each for the year ended December 31, 2005, and other continuous disclosure documents filed by each of them since January 1, 2006 available at www.sedar.com, for further information relating to their mineral resources and mineral reserves.

Cautionary Note to United States Investors Concerning Estimates of Measured, Indicated and Inferred Resources: This news release uses the terms "Measured", "Indicated" and "Inferred" Resources. United States investors are advised that while such terms are recognized and required by Canadian regulations, the United States Securities and Exchange Commission does not recognize them. "Inferred Mineral Resources" have a great amount of uncertainty as to their existence, and as to their economic and legal feasibility. It cannot be assumed that all or any part of an Inferred Mineral Resource will ever be upgraded to a higher category. Under Canadian rules, estimates of Inferred Mineral Resources may not form the basis of feasibility or other economic studies. United States investors are cautioned not to assume that all or any part of Measured or Indicated Mineral Resources will ever be converted into Mineral Reserves. United States investors are also cautioned not to assume that all or any part of an Inferred Mineral Resource exists, or is economically or legally mineable.

Contact Information

  • Denison Mines Corp.
    E. Peter Farmer
    (416) 979-1991 ext. 231
    or
    Denison Mines Corp.
    Ron Hochstein
    (604) 689-7842
    or
    Denison Mines Corp.
    James Anderson
    (416) 979-1991 ext. 372
    (416) 979-5893 (FAX)
    Website: www.denisonmines.com