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Norra Kärr Rare Element Project


Peralkaline intrusion hosted rare earth element and zirconium mineralization, with a bias to the higher value heavy rare earth elements.


Norra Kärr is a zirconium and rare earth element enriched peralkaline (agpaitic) nepheline syenite intrusion which covers 350m x 1200m in area. The project shows geological similarity to REE/Zirconium/Niobium (Nb) mines of the Lovozero province (Russia), and advanced projects at Kipawa Lake (Ontario), Strange Lake (Quebec) and Dubbo (Australia).

The rock units comprising the Norra Kärr intrusion are uncommon on a global scale, and include mineral phases that are comprised of or associated with REE’s, zirconium (Zr), niobium (Nb), yttrium (Y) and hafnium (Hf). Resource calculation by Tasman Metals has shown REE’s to be enriched throughout, with the higher value heavy REE’s comprising greater than 50% of the total REE content.

The Norra Kärr project is low in radioactive metals, and very well serviced by local infrastructure, both of which permit rapid and cost effective exploration and development.


The Norra Kärr project is located in southern Sweden, 15km NNE of the township of Gränna and 300km SW of the capital Stockholm. The project lies in mixed farming and forestry land, well serviced by power, roads and water allowing all year round access, plus the benefit of a skilled and well equipped community.

Tasman Metals Ltd is the 100% owner of the Norra Kärr nr 1 claim covering 549.40 Ha. The claim was granted for a three year period on the 31st of August 2009. The claim can be renewed for additional periods if exploration work has been completed on the project.

In Sweden, a 0.25% royalty is paid on production, shared between landholders and government.


Since granting of the Norra Kärr nr 1 claim, Tasman Metals Ltd have acquired historic exploration data from the Swedish Geological Survey, completed site visits with geological reconnaissance, assayed rock chip samples from trenches and outcrops to confirm the presence of rare earth element and zirconium mineralization, completed a 43-101 technical report, drilled in excess of 40 holes on 100m spaced sections, calculated an Inferred Mineral Resource, and initiated metallurgical testing with SGS Lakefield (Canada).

Drilling of the Norra Kärr rare earth element project began in early December 2009, only 1 month after Tasman Metals Ltd was listed on the TSX.V. A resource calculation was completed on the project within 12 months of this first ever drilling program. A Phase 3 program began in January 2011 to infill drill sections to 100m spacing.


Unusual intrusive rocks and the associated fennite aureole at Norra Kärr were first described in 1906 by the Swedish government geologist Alfred Törnebohm, who named the site after the local farm. Törnebohm revisited the site a few years later to collect samples – the rock types and minerals described from that visit remain valid until today.

Principal exploration in the area was conducted by Swedish mining company Boliden AB. The first activity occurred during and after the second world war, as Sweden sought self sufficiency for strategic minerals and energy., when the company investigated the Zr and nepheline potential of the grännaite.

In 1948 Boliden AB signed a contract with the landholders which gave them rights to mine. Test pitting at two sites and subsequent trial enrichment began in 1949. Boliden AB determined that with technology of the day separation of nepheline from feldspar and aegerin was difficult and the Fe grades were elevated. Profitable Zr extraction was not shown to be successful, due to the synchronous discovery and development of rich deposits of monazite and zircon in Brazil.

In 1974 Boliden AB re-started exploration for nepheline, zirconium and hafnium. During the 1970’s Boliden sampled two long trenches 400m apart across the intrusion, returning:

NORTH TRENCH 244m at 1.9% ZrO2, 0.37% TREO*
SOUTH TRENCH 149m at 1.49% ZrO2, 0.43% TREO; and 52m at 1.47% ZrO2, 0.54% TREO

*TREO = total rare earth oxide + yttrium oxide (Y2O3); ZrO2 = zirconium oxide;

Although “TREO” is quoted above, samples taken by Boliden were not assayed for 6 of the 9 higher value, heavy rare earth elements (HREE’s). Twenty-seven random, non-representative rock samples submitted for assay by Tasman has confirmed the presence of HREE’s in the Norra Kärr intrusion. The 27 samples ranged from 0.09% to 0.7% and averaged 0.35% TREO. Weight percent of HREO (heavy rare earth element oxides) relative to TREO ranged from 24 – 68% and averaged 54%, showing Norra Kärr to be elevated in the higher value HREE’s relative to light rare earth elements (“LREE”).

Norra Kärr lay on free ground from Boliden’s exit in 2001 until Tasman’s acquisition in 2009.


The rock units comprising the Norra Kärr peralkaline (agpaitic) intrusion are uncommon on a global scale, and include mineral phases that are comprised of or associated with REE’s, Zr, Nb, Y and Hf. The most abundant intrusion present is grännaite, a foliated fine grained rock consisting of alkali feldspar, nepheline, aegirine, eudialyte and catapleite. Lesser units include lakarpite (arfvedsonite-albite nepheline syenite), pulaskite (microcline-arfvedsonite-albite nepheline syenite) and kaxtorpite (pectolite-eckermannite-aegirine-nepheline syenite). Intervals of irregular coarse grained pegmatite schlieren with equivalent mineralogy to the grännaite are also commonly developed. The Norra Kärr intrusion area is surrounded by a 25-100m wide fennite aureole.

The nepheline syenite intrusion is hosted by a coarse grained microcline rich regionally significant granite (the Växsjö granite), the contacts between which are deformed with a clear schistosity. The Norra Kärr intrusion is interpreted to be part of the Neoproterozoic North Atlantic Alkaline Province, having been dated at 1547±62 Ma (Blaxland, 1977), with equivalent age alkaline rocks known from southern Greenland and northern Canada.


The first NI 43-101 compliant independent resource estimate for Norra Kärr was released on the 30th November 2011. The resource estimate was prepared by Pincock Allen & Holt (“PAH”) / Minarco-Mineconsult (both subsidiaries of Runge Ltd). Mineral resources were modelled by PAH applying five different total rare earth oxide (TREO) cut-off grades, with a base-case resource estimated using a TREO cut-off of 0.4%. At this cut-off, Norra Kärr hosts an Inferred Mineral Resource of 60.5 million tonnes grading 0.54% TREO and 1.72% ZrO2 (zirconium oxide), with 53.7% of the TREO being the higher value HREO (heavy rare earth oxide). The second table below illustrates the grade averages for all of the rare earth oxides at the various cut-offs.

Table 1: Inferred Resource Estimate for the Norra Karr Deposit.

TREO % Cut-off Million Tonnes TREO % % of HREO in TREO ZrO2 % HfO2 % Tonnes of Contained TREO  
0.6 16.2 0.66 52% 1.80 0.033 106,900
0.5 38.4 0.60 52% 1.75 0.034 230,400
0.4 60.5 0.54 53% 1.72 0.034 326,700 BASE CASE
0.3 77.9 0.50 54% 1.70 0.035 389,500
0.2 99.3 0.45 53% 1.60 0.034 446,800



  1. Total Rare Earth Oxides (TREO) includes: La2O3, Ce2O3, Pr2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, Lu2O3, Y2O3
  2. Heavy Rare Earth Oxides (HREO) includes: Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, Lu2O3, Y2O3
  3. The calculated resource is sensitive to cut-off grade which will be influenced by metallurgical operating costs. Tasman is advancing its rare-earth metallurgical studies at SGS Lakefield (Canada) assisted by consulting metallurgist Les Heymann, with the aim of developing a cost-efficient and effective metallurgical flowsheet.
  4. The mineral resource estimate was completed by Mr Geoffrey Reed, Senior Consulting Geologist of Minarco-Mineconsult (Australia), and is based on geological and geochemical data supplied by Tasman, audited by Mr Reed. Mr Reed is an independent qualified person for the purposes of NI 43-101 standards of disclosure for mineral projects of the Canadian Securities Administrators and has verified the data disclosed in this release. A Technical Report with the estimate will be filed on SEDAR within 45 days.
  5. The resource estimate has been classified as an Inferred Resource due to the wide-spaced sample data within the current deposit outline.
  6. The resource estimate is based on:
    • A database of 26 drill holes totalling 3,276m of diamond drilling completed by the Company since December 2009 where samples were composited on 2m lengths. Assays were completed at ALS Chemex, with check sampling completed by ACME Laboratories Ltd.
    • Specific gravity (SG) used the overall mean of 2.70 g/cc from 179 SG readings.
    • Block model was estimated by inverse distance squared interpolation method on blocks 100m x 20m x 20m.
    • Metallurgical test work at Norra Karr is in progress and no information was available at the time of this resource calculation.

The drill-defined inferred Mineral Resource at Norra Kärr begins at surface and is open at depth and to the south. As recommended by PAH, Tasman intends to advance the understanding of the project with additional higher-density diamond drilling, planned to take place from December 2010. Mineralogical and metallurgical research is underway, led by SGS Minerals Services of Canada. It is intended that the data from these studies will form the basis for a future Scoping Study of the deposit.

0.2 99.3 0.042 0.091 0.012 0.047 0.010 0.002 0.015 0.003
0.3 77.9 0.048 0.105 0.014 0.053 0.011 0.002 0.016 0.003
0.4 60.5 0.054 0.117 0.015 0.059 0.012 0.002 0.018 0.004
0.5 38.4 0.060 0.134 0.017 0.067 0.012 0.002 0.020 0.004
0.6 16.2 0.065 0.149 0.019 0.075 0.012 0.003 0.022 0.004


0.2 99.3 0.022 0.005 0.016 0.003 0.016 0.002 0.161
0.3 77.9 0.024 0.005 0.017 0.003 0.017 0.002 0.178
0.4 60.5 0.026 0.006 0.018 0.003 0.017 0.002 0.190 BASE CASE
0.5 38.4 0.027 0.006 0.019 0.003 0.017 0.002 0.206
0.6 16.2 0.030 0.006 0.020 0.003 0.019 0.003 0.232


A 100 kg sample was sent to SGS Lakefield (Canada) in November 2011. QEMSCANTM results confirmed that the principal REE and zirconium bearing phases are zirconium silicates. Eudialyte is most abundant zirconium silicate comprising 4.3% of the 100kg sample, whilst secondary is catapleiite comprising 2.5%. Zircon and other REE phases are present in only trace amounts. Other minerals in the sample are dominated by Na-Al silicates (36%), plus nepheline/microcline (31%) and clinopyroxene (24%).

The liberation and association characteristics of the zirconium silicates after crushing were examined. Particle liberation describes the degree of separation of minerals-of-interest from other minerals, based on the 2 dimension mineral-of-interest area percent. Perfect liberation therefore equals 100%. Liberation analysis of the Norra Karr sample indicated that in crushed material where 80% passed -150 μm, 79% of zirconium silicates were well liberated (where ≥80% of the mineral-of-interest is separated from other minerals). This is considered to be a high and encouraging degree of liberation.

The calculation of exposed surface area of the zirconium silicates after crushing indicates that a large portion of grains (up to 94% of the mass) had a surface exposure area greater than 50%. This well exposed surface area suggests good potential for recovery, as the minerals of interest are well exposed for chemical attack and breakdown, the metallurgical effect of which must be tested with extensive research.

In May 2011, Tasman reported on the first leach tests carried out on the Norra Karr project. Three roast and leach tests have been performed to date by SGS on this representative sample without any pre-concentration process. The roast and leach process has been applied to a pulverized sample of ore. The third such test (NK3 in Table 1 below) was extremely successful, where a pre-leach at room temperature was followed by acid roast and leach, which successfully brought into solution in excess of 90% of all REE’s and Zr. Table 1 below provides a compilation of recovery for various leach tests performed on equivalent samples.

Table 1: Percentage recovery of key elements, and conditions of roast and leach testing

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Sc Y Zr Fe Si
NK-1 58.3 56.6 56.4 56.2 51.4 49.0 48.3 46.5 46.0 43.4 44.3 43.3 43.1 42.7 37.3 47.0 61.4 8.5 1.0
NK-2 65.0 61.9 52.1 64.3 51.2 48.8 65.0 64.2 64.2 63.3 62.1 62.2 62.2 61.2 53.3 61.3 65.9 7.7 0.3
NK-3 96.7 95.4 97.1 97.1 96.4 95.9 95.4 94.4 93.5 92.7 92.8 92.3 92.1 91.4 74.4 92.9 91.1 3.7 3.5

NK-1: crushed ore where 80% of the sample passed a 24.6 micron screen; combined with 600 kg/tonne of ore of sulphuric acid, roasted for 4 hours at 150 degrees C

NK-2: crushed ore where 80% of the sample passed a 52.2 micron screen; combined with 2000 kg/tonne of ore of sulphuric acid, roasted for 4 hours at 150 degrees C

NK-3: crushed ore where 80% of the sample passed a 52.2 micron screen; combined with leaching solution at room temperature. This solution removed, then ore combined with 600 kg/tonne of ore of sulphuric acid, then roasted for 4 hours at 150 degrees C

Preconcentration methods continue to be researched. The roast and leach method used in sample NK3 will now be further optimised to further enhance its effectiveness and reduce potential processing costs, including advancing research into flow-sheet optimization, aiming to reduce grinding and heating requirements and reagent consumption, reduce leach times, maximize REE recoveries and reduce recovery costs.







Mon May 2, 2011 Tasman Further Expands Thickness of Drilled Mineralization at Norra Karr Heavy Rare Earth Element and Zirconium Project, Sweden
Thu Apr 28, 2011 Tasman Board Approves Expansion of Phase 3 Drilling Program at Norra Karr Heavy Rare Earth Element and Zirconium Project
Tue Apr 26, 2011 Tasman Drills Thickest Interval of Heavy Rare Earth Elements and Zirconium at Norra Karr, Sweden