 TARGET Skarn associated rare earth element and lead mineralization, with preferential enrichment of Ce, La, Nd. OVERVIEW Korsnäs is a rare earth element (REE) and lead (Pb) enriched skarn which was mined by Outokumpu Oy as a mixed open pit and underground operation from 1959 to 1972. REE-Pb mineralization occurs within a north-south trending skarn zone comprised of coarse-grained calcite, feldspar, diopside, apatite, galena, scapolite, fluorite and barite hosted by a regional mica gneiss. The mined and drill defined ore body is approximately 20m thick, is known to trend over a strike length of greater than 300m, and extends from surface to a vertical depth of 175m. Based on limited sampling of rare earth element bearing minerals by Papunen et al. 1986 (Suomen malmigeologia), Ce, La and Nd comprise 80 -- 90 % of the REE's present, the balance consisting principally of Pr and Sm. Outokumpu Oy's business focus at the time of mining was base metals and mining was therefore focused to maximize Pb, not REE grades and recoveries. While the former mining features of the site have been rehabilitated, the Korsnäs project lies close to the Baltic coast and remains very well serviced by local infrastructure, which shall permit rapid and cost effective exploration and development . LOCATION, OWNERSHIP, CLAIM STATUS The historic Korsnäs REE-Pb mine is located in central western Finland, 350 km north of Helsinki and only 25 km southwest of the Baltic Sea port town of Vaasa. The project is a rehabilitated former minesite, with some mine buildings remaining intact. Due to its mining history, the site is well serviced by power, roads and water allowing all year round access, plus the benefit of a skilled and well equipped community. Tasman has acquired a 100% interest in the former mine by staking the Korsnäs 1-4 claim applications that total 268 hectares, and 6,652 hectares of surrounding claim reservations. Applications for claims were submitted following a presentation to and discussion with local community leaders by Tasman Metals Ltd's personnel. It is anticipated that the claims will be granted during 2010 for a period of three years, whilst the claim reservations were granted during November 2009 for a period of one year. RECENT WORK Since acquisition of the Korsnäs project, Tasman Metals Ltd have initiated discussion with local community representatives as to future plans and potential for the project, and are now in the process of acquiring and compiling the extensive technical data from the project. This technical data provides information on the geological, mining and mineral processing status of the project. PROJECT HISTORY Korsnäs was first identified in 1950 through the discovery of Pb sulphide-bearing glacial boulders. In the 1950's, the Geological Survey of Finland followed up the mineralized boulders with various geochemical and geophysical methods and diamond drilling which led to the discovery of the REE-Pb deposit in 1955. Between 1959 and 1972, Outokumpu Oy produced a total of 0.87 million tonnes of ore at a grade of 3.6% Pb and 0.83% REE's. This production estimate is based on a report titled "Outokumpu Oy:n Korsnäsin ja Petolahden kaivosten vaiheita" by Reino Himmi in 1975. Korsnäs was operated as a mixed open pit and underground operation, and closed due to falling Pb prices. A REE concentrate was produced on site, proving the amenability of the ore for processing and providing an excellent basis for Tasman's future metallurgical research. In addition to the Korsnäs mine site, gravity, seismic refraction surveys and diamond drilling have been conducted by the Geological Survey of Finland and Outokumpu Oy within the claim reservations held 100% by Tasman that lie south of Korsnäs. This work has indentified skarnified fault zones with the same mineralogy as Korsnäs, plus numerous REE- and Pb- rich glacial boulders. Tasman has access to all publically available exploration data and drill core from the Geological Survey of Finland and Outokumpu Oy. This information is currently being compiled and verified, the detail of which will be released as it comes to hand. GEOLOGY AND MINERALIZATION REE-Pb mineralization occurs within a north-south trending skarn zone comprised of coarse-grained calcite, feldspar, diopside, apatite, galena, scapolite, fluorite and barite hosted by a regional mica gneiss. The mined and drill defined ore body is approximately 20m thick, is known to trend over a strike length of greater than 300m, and extends from surface to a vertical depth of 175m. Ore resources remaining at the conclusion of mining have not yet been determined. It remains unknown to what extent mineralization continues along strike and at depth from the mined out areas. Apatite, monazite and allanite are the principal REE minerals present at Korsnäs, although the site is well known for numerous exotic rare earth element minerals. Based on limited sampling of rare earth element bearing minerals by Papunen et al. 1986 (Suomen malmigeologia), Ce, La and Nd comprise 80 -- 90 % of the REE's present, the balance consisting principally of Pr and Sm (see Table 1 for a full list of rare earth elements). 43-101 AND OTHER TECHNICAL REPORTS PRESS RELEASES PHOTOS AND MAPS
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Aerial view of Korsnas REE-Pb mine and plant when operating. Site has now been rehabilitated, the tailings dam covered, and mining equipment removed | |
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