Duluth Metals Announces Increased Tonnage, Metal Content and an Upgraded Measured Classification in new updated AMEC Resource Study on the Twin Metals Project

-- Using a base case 0.3% Cu cut-off, AMEC estimated a Measured Mineral Resource of 295 million tons, an Indicated Mineral Resource of 977 million tons¹, and an Inferred Mineral Resource of 1.313 billion tons on four deposits (Maturi, Maturi Southwest, Birch Lake and Spruce Road) occurring on approximately 13% of the footprint of the prospective portion of the Twin Metals Minnesota (TMM) property block.

-- The AMEC update confirms an increase in contained metal for all products: copper, nickel, palladium, platinum and gold.

-- Exceptional continuity and correlation in the closely spaced Maturi Deposit fence drilling results enabled AMEC to upgrade a portion of the Maturi deposit to the Measured classification.

-- The AMEC updated mineral resource estimate highlights a growing Platinum Group Metal (PGM) and gold resource of 5.0 million ozs Measured, 17.2 million ozs Indicated and 13.4 million ozs Inferred in the Maturi, Maturi Southwest and Birch Lake deposits. The TMM project has one of the world's largest palladium and platinum resources outside of South Africa.

TORONTO, Feb. 26, 2014 /PRNewswire/ -- Duluth Metals Limited ("Duluth", "Duluth Metals") (TSX: DM) (TSX:DM.U) today announced that it has received an updated draft NI 43-101 Technical Report on the consolidated mineral resources for the Twin Metals Minnesota Project in Northeastern Minnesota prepared by an AMEC E&C Services Inc. (AMEC) team led by Dr. Harry Parker, RM, SME. This updated study utilizes 916 drill holes and 312 wedge offsets, and reports a significant portion of the Maturi deposit upgraded to the Measured Resource category. A full report will be filed in 45 days on www.SEDAR.com.

The majority of the increase in total contained metals in the 2014 resource estimates reflects the addition of the Maturi Southwest Deposit. The change in category for a significant portion of the Indicated Resource to Measured Resource reflects the excellent continuity of the resource demonstrated by the close spaced fence drilling completed at Maturi. The new classification by category is shown in the following table:

Table 1 - Contained Metals in the TMM Resource (effective date October 8, 2013)*

* Note - Based on mineral resources estimated at base case 0.3% copper cut-off grade; for tons and grade see Tables 2-5 in this press release.

** Note - Contained ounces of platinum, palladium, and gold in the Inferred category do not include the Spruce Road deposit.

¹ All tonnages are reported as short tons.

Vern Baker, President of Duluth Metals, commented: "The ability of the Twin Metals Project to move 295 million tons of resource into the Measured category confirms the excellent consistency of the mineralized material in the Maturi Deposit. It is early in the project development cycle to have such a large Measured Resource. The potential scale of the project resource is exceptional, considering that only 13% of the prospective portion of the Twin Metals Property contains such a large total resource of Measured, Indicated, and Inferred tonnage."

Significant Tonnage in the Measured Category
The study includes four mineral resources in close proximity to one another within the Twin Metals Minnesota Project, referred to as the Maturi, Maturi Southwest, Birch Lake, and Spruce Road Deposits. The updated mineral resources estimate has 295 million tons in the Measured category at a 0.3% copper cut-off in the Maturi Deposit, which may potentially provide an early start-up area for future mining. The Maturi Deposit resource estimate does not incorporate new assay or geological data from drilling results received after September 15, 2012. The Maturi Southwest Deposit is a newly classified resource which was defined by drilling in 2013:

• Using a base case 0.3% Cu cut-off, the Maturi Deposit** contains 295 million tons of Measured Mineral Resources grading 0.63% copper, 0.20% nickel, 0.58 parts per million TPM (TPM = Pt + Pd + Au) and 774 million tons of Indicated Mineral Resources grading 0.58% copper, 0.19% nickel, 0.61 parts per million TPM, plus an additional 562 million tons of Inferred Mineral Resources grading 0.51% copper, 0.17% nickel, 0.53 parts per million TPM. (Note: Full grade and tonnage tabulation is shown in the Detailed Resource Tabulations section later in this press release)
• Using a base case 0.3% Cu cut-off, the Maturi Southwest Deposit** contains 103 million tons of Indicated Mineral Resources grading 0.48% copper, 0.17% nickel, 0.31 parts per million TPM, plus an additional 32 million tons of Inferred Mineral Resources grading 0.43% copper, 0.15% nickel, 0.26 parts per million TPM.
• Using a base case 0.3% Cu cut-off, the Birch Lake Deposit** contains 100 million tons of Indicated Mineral Resources grading 0.52% copper, 0.16% nickel, 0.86 parts per million TPM, plus an additional 239 million tons of Inferred Mineral Resources grading 0.46% copper, 0.15% nickel, 0.64 parts per million TPM
• Using a base case 0.3% Cu cut-off, the Spruce Road Deposit** contains 480 million tons of Inferred Mineral Resources grading 0.43% copper, 0.16% nickel.*

* Note - The Spruce Road resource was estimated using Inco legacy assay data. Platinum, palladium, and gold were not assayed by Inco, and the core is not available for re-assay.

** Note - These mineral resource estimates include 100% of the estimated resource in each deposit, and include interests in mineral resources held by Franconia Minerals (US) LLC (f.k.a. Franconia Minerals Corporation), a wholly-owned subsidiary of Twin Metals. Twin Metals acquired 100% of the ownership units of Franconia in 2011. Franconia's principal assets are a 70% interest in the Birch Lake, 'old' Maturi, Maturi Southwest, and Spruce Road deposits in northeastern Minnesota through the Birch Lake Joint Venture. Franconia announced in November, 2010 its intention to increase its ownership at the Birch Lake Joint Venture to 82%; see Franconia's company profile at www.SEDAR.com for Technical Reports. TMM's ownership of the resource will be factored by these percentages where applicable.

Updated Mineral Resources
Twin Metals Minnesota LLC, is the joint venture company between Duluth Metals Limited (60% ownership interest) and Antofagasta plc (40% ownership interest). In 2011, Twin Metals Minnesota LLC acquired Franconia Minerals Corporation. Franconia`s principal assets are a 70% interest in the Birch Lake, "old Maturi" (not including former Nokomis property), Maturi Southwest, and Spruce Road deposits through the Birch Lake Joint Venture, with Beaver Bay, Inc., owning the remaining 30%. Franconia announced in November, 2010 its intention to increase its ownership at the Birch Lake Joint Venture to 82% upon commencement of production. All of the forgoing Indicated and Inferred Mineral Resources, and Exploration Target tonnages are expressed as a 100% ownership position.

The Mineral Resource estimate for the Maturi deposit incorporates assay data from 444 drill holes and 154 wedge off-set holes totalling 1,328,000 feet drilled on the Maturi deposit between 2006 and 2012, in addition to information from 99 legacy holes also in the geologic data base. The effective date of the Maturi mineral resource estimate is October 8, 2013. The Maturi Southwest deposit resource estimate incorporates assay data from 49 drill holes and four wedge off-set holes totalling 46,000 feet drilled in 2013, and information from an additional six legacy holes. The effective date of the Maturi Southwest mineral resource estimate is June 15, 2013.The Birch Lake deposit resource estimate incorporates assay data from 97 drill holes and 146 wedge off-set holes totalling 297,000 feet drilled between 2000 and 2012, and information from an additional 17 legacy drill holes and 8 wedge off-set holes. The Spruce Road deposit resource estimate incorporates assay data from 210 legacy holes. The effective date of the Birch Lake and Spruce Road mineral resource estimates is September 15, 2012. The mineral resources have been estimated using CIM Definition Standards for Mineral Resources and Reserves dated November 2010.

Detailed Resource Tabulations
Tables of the updated mineral resource tons and grades for various cut-offs are shown below for each deposit. The base case (0.3% Cu cut-off) is highlighted. The remaining cases are included to show the sensitivity of the estimates to changes in cut-off grades:

Table 2 - Maturi Deposit Measured, Indicated, and Inferred Mineral Resources (effective date October 8, 2013)

• Maturi Deposit tonnages do not include 114 million tons of mineralized material excluded from the underground resource in a crown pillar.
• CIM Definition Standards (2010) were followed for Mineral Resource estimation and classification.
• TPM is defined as Au + Pt + Pd.

Table 3 - Maturi Southwest Deposit Indicated and Inferred Mineral Resources (effective date June 15, 2013)

Table 4 - Birch Lake Deposit Indicated and Inferred Mineral Resources (effective date September 15, 2012)

Table 5 - Spruce Road Deposit Inferred Mineral Resources (effective date September 15, 2012)

Exploration Target Area Tonnage and Grade Ranges
Additional exploration potential highlighted by AMEC outside of the four mineral resources (Maturi, Maturi Southwest, Birch Lake and Spruce Road deposits) and in addition to the TMM defined mineral resource are considered targets for further exploration.

An estimate of the exploration potential is between 1.3 to 2.1 billion tons contiguous to the boundaries of the four deposits. These exploration target areas occur on approximately 13% of the footprint of the prospective portion of the TMM property block. The grade and tonnage ranges of the four exploration targets are based on limited drill hole results and location within the favourable host rocks. The potential quantity and grade of the exploration target areas are conceptual in nature, and there has been insufficient exploration to define the target as a mineral resource, and it is uncertain if further exploration will result in the target being delineated as a mineral resource.

Maturi
An estimate of the exploration target potential for Maturi North and Maturi South were determined by estimating a range of the tons within the modeled area at a range of the grades that are known to occur within that deposit area. Tonnage and grades of the Maturi North exploration target could range from 290 to 430 Mst (million short tons) grading 0.41 to 0.61% Cu, 0.14 to 0.21% Ni, 0.10 to 0.15 ppm Pt, 0.23 to 0.34 ppm Pd and 0.05 to 0.08 ppm Au. Tonnage and grades of the Maturi South exploration target could range from 330 to 500 Mst (million short tons) grading 0.42 to 0.62% Cu, 0.13 to 0.19% Ni, 0.14 to 0.21 ppm Pt, 0.31 to 0.46 ppm Pd and 0.07 to 0.10 ppm Au.

Maturi Southwest
The estimated exploration target potential within the permit boundaries are based in part on mineralized intercepts from 11 drill holes; of these 7 are legacy drilling and 4 are recent Maturi Southwest (MSW) drill holes. Internal to the MSW exploration target is a low-grade area (below 0.30 % copper); this area was excluded from the estimated exploration target tonnage ranges. The southern boundary of the MSW exploration target was truncated against the exploration area defined for the Birch Lake. The tonnage potential of the MSW exploration target area could range from 500 to 820 Mst (million short tons) with grades ranging from 0.43 to 0.55 %Cu, 0.14 to 0.18 %Ni, 0.08 to 0.10 ppm Pt, 0.17 to 0.22 ppm Pd and 0.03 to 0.07 ppm Au.

Birch Lake
At Birch Lake, blocks with extrapolated grades outside the area classified as Inferred are considered to be targets for further exploration. Exploration potential is in the range of 220 to 330 Mt and with grades ranging from 0.33 to 0.50% Cu, 0.11 to 0.16% Ni, 0.11 to 0.16 ppm Pt, 0.22 to 0.33 ppm Pd, and 0.05 to 0.08 ppm Au. The range of tonnage and grade is based on a 0.30% Cu cutoff of material outside of the Inferred Classification boundary using a range of grades that are known to occur within the favourable host rocks.

About the Resource Estimates
The figures for resources presented herein, including the anticipated tonnages and grades that may be achieved or the indicated level of recovery that may be realized, are estimates, and no assurances can be given that they will be realized during production. Such estimates are, in large part, based on interpretations of geological data obtained from drill holes and other sampling techniques. Actual mineralization or favourable host rock units may be different from those predicted. It may also take many years from the initial phase of drilling before production is possible, and during that time the economic feasibility of exploiting a deposit may change.

Duluth's business of mineral exploration has a high level of inherent risk. Although Duluth is optimistic about the potential of many of its projects, there is no guarantee that any mineral deposits will be economically feasible and that these deposits will be put into production. Duluth's exploration and development activities may also be affected by a number of risks, including environmental, metallurgical, financing, permitting, approval, legislative and other government risks which are common to the industry and are referenced in greater detail in the Company's Annual Information Form.

For the non-legacy assay data utilized in these resource estimates, half core samples were prepared at ALS Minerals laboratories in Thunder Bay and then shipped to the ALS analytical facilities in Vancouver. Samples were analyzed for Au, Pt, and Pd using a 30g standard fire assay with an ICP-AES finish. An additional 33 elements were analyzed for using a four acid (near total) digestion and a combination of ICP-MS and ICP-AES. ICP over-limits for copper and nickel are re-analyzed using dissolution four acid (near total) digestion followed by ICP-AES or AAS. The remaining half core samples are being stored in Minnesota. A system of blanks, standards and quarter-core duplicates were added to the sample stream by Twin Metals Minnesota LLC to verify accuracy and precision of assay results, supplementing and verifying a variety of internal QA/QC tests performed by ALS Minerals.

The Maturi resources are based on a concentrate sales plan that in turn assumes a mining cost of $12.54/t, a process cost of $5.96/t and general and administrative charges of $3.16/t. The prices, recoveries, and payabilities are shown in the table below. The metal prices used in the NSR calculation were mutually agreed upon by Duluth, TMM, Antofagasta plc and AMEC on February 4, 2014.

2013 Maturi NSR Parameters (US$)

All data verification and quality assurance/quality control procedures of Twin Metals Minnesota LLC were applied specifically to the results contained in this press release, and the data herein have been verified by Phillip Larson, P. Geo., Senior Geologist with Duluth Metals and a Qualified Person under NI 43-101, in accordance with the procedures of the Company. The data verification procedures and quality assurance/control procedures adopted by the Company and applied to the work being reported in this press release can be found in Section 11 of the "NI 43-101 Technical Report on the Maturi, Birch Lake, and Spruce Road Copper-Nickel-PGE Projects, Ely, Minnesota, USA", with an effective date of June 15, 2012, and dated July 27, 2012. The Technical Report was filed on SEDAR under the Company's profile on July 27, 2012 (www.sedar.com).

Dr. Harry Parker, SME, Registered Member, Technical Director of AMEC, is the Independent Qualified Person who prepared the Resource Estimate and is responsible for the mineral resource estimates summarized in this press release. Dr. Parker is a licensed Professional Geologist in the State of Minnesota. Phillip Larson, P. Geo. is the Qualified Person for Duluth Metals and Senior Geologist for Duluth Metals, in accordance with NI 43-101 of the Canadian Securities Administrators, and reviewed and approved the technical content of this press release.