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Superb Lake



The Superb Lake property consists of 8 mining claims totaling approximately 2,187 hectares land in the  O’ Sullivan Lake / Maun Lake Area, Thunder Bay Mining District of Northwestern Ontario, Canada. It is located about 375 kilometers northeast of Thunder Bay, with the nearest town to the property situated 45 km to the south of the Property.


The property is situated in the eastern part of Wabigoon Subprovince of the Superior Geological Province. This Subprovince consists mainly of Archean metavolcanic and metasedimentary rock sequences intruded by larger granitoid plutons, mainly granodiorite to granite in composition. The property is in the Onaman-Tashota geological belt which straddles the entire width of the eastern Wabigoon subprovince. The metavolcanics comprise minor ultramafics and abundant mafic to felsic rocks. The assemblage is in faulted contact with the metasedimentary rocks of the English River subprovince. The assemblage is accompanied by quartz porphyry dikes that transect the mafic metavolcanic strata and mafic and felsic intrusions across the width of O’ Sullivan Lake area. The metasedimentary rocks are composed of medium to thinly bedded, locally garnetiferous, biotite-quartz-feldspar wackes, belonging to English River assemblage which hosts the Superb Lake lithium pegmatite exposed along the northwest shoreline of Superb Lake. This lithium-rich pegmatite was apparently discovered around 1955. Several strong, northerly trending faults 020?040 degrees have been identified in the area. The Hurd Lake Fault Zone occurs within the Northeastern end of the Kowkash Greenstone Belt where the belt appears to start pinching out at O'sullivan Lake. The fault is a northeast trending (040 to 045 degrees) structure with numerous parallel copper-gold showings associated with it. The Superb Lake pegmatite is known principally for its spodumene bearing lithium and niobium / tantalum mineralization.


The Property area has two types two types of deposit models which are:

  • Pegmatite type lithium and rare metals deposits
  • Mesothermal Archean lode gold deposits

Superb Lake area has had historical exploration work carried out since the 1950s’ discovery of   lithium along the shores of Superb Lake. In 2003, Ontario Geological Survey  (OGS)  carried   out  regional  investigation   of  mineralization  associated   with  rare  element pegmatites and related S-type, peraluminous granites in the Superior Province of Ontario.  A part   of  this  work   was  carried  out   on  the  Superb   Lake  pegmatite  within   the  Property  Area.   This work  included  mineralogical   and  petrochemical  detection   of  fertile,  peraluminous   parent  granites  coupled   with  regional  sampling   aimed  at  discerning   exomorphic dispersion in the host rocks adjacent to rare-element pegmatites. The Superb Lake pegmatite has a minimum exposed strike length of 16 m and its width varies from 2.5  m at the shoreline to a maximum of 3.7 m where an old blast pit was excavated. A large  bulk  sample   collected  from  the   pegmatite  by G.M.  Stott   from  the  blast   pit  area  in   1988  contained Ta above  the detection limit of 350 ppm, 142 ppm Be, 80 ppm Nb, 1464 ppm  Rb, 99 ppm Cs and 56 ppm Sn.   

Summer 2022 exploration work on the property included  prospecting,   geological  mapping,  sampling,   ground  geophysical surveys and assaying. A total of 26 grab rock samples were collected out of which eight samples were from  the  Superb   Lake  Pegmatite  outcrops,   18  were  from   historical  gold  showing   in  the  Holm   Area.

Superb Lake pegmatite has spodumene as a principal lithium mineral which occurs in this   pegmatite  as  large  isolated   crystals  in  a   relatively  fine-textured  groundmass   of  feldspar,  quartz, mica and other minerals, and to a lesser extent as a part of the groundmass itself.   The results of  four samples taken  from spodumene rich part indicate lithium oxide  (Li2O)   values in the range of 1.77 % to 4.03%. Several narrow, aplite-like veins are situated within  30 m of  the main pegmatite and  reveal important evidence  for   the style of deformation.  Four samples taken from aplite dykes indicate Li2O values in the range of <0.01% to 0.02%.

The  results of sampling  from Holms Area indicate gold values in  the  range of less   than 5  parts per billion  (ppb)   to over 5,000 ppb using method “Au - Fire Assay AA”. The sample   884871 exceeded  the method  detection   limit and  was  retested   using method  “Au - Fire Assay Gravimetric” and gave assays of 29.6 gram per tonne gold.

A VLF and ground magnetic survey was completed on Polpond Grid during June 25 to July  04, 2020 with a total 20.5 line-km at 50m line spacing and 25m stations. Similarly, a second  magnetic / VLF was completed on the Holm Grid from July 12-19, 2020 with a total 15 line? km  at   50m  line  spacing   and  25m  stations.   The  results  of   the  Polpond  survey   indicate  presence  of   an  east-west  running   conductor  extending  for   about  800  meters   in  the  northwest part of the survey area.   

The  results  of   the  Holm  survey   grid  show  two   separate  roughly  east-west   oriented  conductive  zones   separated  by  a   resistive  zone.  Each   conductive  zone  is   over  one  kilometer in length and is marked by isolated conductive bodies.

Medaro has not carried out any exploration work on the Property.  The author visited the  Property on September 06, 2020  to verify historical exploration work including  trenching  and   sampling work,  to examine mineralized  outcrops and  to   collect  necessary geological  data. A total of five grab rock samples were collected by the author from the Superb Lake   pegmatite  outcrops,  host   metasedimentary  rocks,  and   other  exploration  areas.   The  samples were delivered to ACTLABS in Thunder Bay, Ontario for analyses. All samples were  under the care and control of the author and are considered representative. The samples   were  assayed  by  ACTLABS  using   Laboratory  Code  8:   ICP-MS  PerOxide  Fusion   (FUS-MS-Na2O2).  The  samples   assays  indicated  lithium   (Li)  values  in   the  range  of   0.0037%  Li  (0.008% lithium oxide) to 1.51% Li (3.25% lithium oxide), beryllium (Be) is in the range of  less than 3 parts per million (ppm) to 156 ppm, cesium (Cs) 39.7 ppm to 165 ppm, niobium   (Nb)  8  ppm   to  153.5  ppm,   and  tantalum  (Ta)   0.9  ppm  to   578  ppm.  These   results  are  consistent with historical exploration results.

The  data  presented in   this  report is  based   on  published  reports and   data available  from  Medaro,   Ontario  ENDM  (Ministry   of  Energy,  Northern   Development  and  Mines),   the  Geological Survey of Canada, and the Ontario Geological Survey. All consulted data sources  are   deemed  reliable.  The   data  collected  during   present  study  is   considered  sufficient  to   provide an opinion about the merit of the Property as a viable exploration target.  

Exploration Targets

Based on its favourable geological setting indicating spodumene bearing pegmatite hosted lithium and rare metals mineralization in surface grab samples and trenches; gold and base  metals anomalous values found on surface and drill holes; and findings of present study, it  is concluded that the Superb Lake Property has good potential for discovery of economic concentration of lithium and gold mineralization through further exploration. Good infrastructure and availability of exploration and mining services in the vicinity makes it a worthy mineral exploration target.

Phase 1 – Geophysical and Geochemical Surveys, Prospecting, Trenching and Sampling

There are two types of mineralization and deposit types identified for the Property which need a focussed exploration work for each type as follows:  

  • Superb  Lake   Pegmatite  –  this   pegmatite  is  known   principally  for  its   spodumene  bearing  lithium   and  niobium  /   tantalum  mineralization.  It   is  recommended  to   conduct  trenching  and   channel  sampling  along   the  strike  extension   of  the  pegmatite. Another recommendation is  to carry out ground magnetic /VLF survey  and   soil  geochemistry  in   the  areas  adjacent   to  the  pegmatite   and  associated  granitic intrusion.
  • Gold and Base Metals Exploration - The Property is located to the north along the  same  fault   trend  as  the   past  producing  Louisianna   Gold  Mine.  There   are  a  few   historical mineral showings on the Property, and it is recommended that the area  around these occurrences should be prospected to find more showings for further   exploration. Polpond VLF survey grid should be extended to the west and Holm VLF  survey  grid   should  be  extended   to  the  east   to  see  the   continuity  of  conductors   identified during 2020 geophysical surveys.

Phase 2 – Diamond Core Drilling

If   results  from the   first  phase  are   positive,  then  a   detailed  drilling  program   would  be  warranted   to  check  the   most  promising  targets   identified  because  of   geophysical  and  geochemical   surveys,  trenching,  and   sampling  work  in   Phase  1.  The   scope  of  work   for  drilling and location of drill holes would be determined based on the  findings of Phase 1  investigations.