The principal lead and zinc mineralized BIF is termed Lens B, it is around 2 to 8 m thick. ![]() Mineralization is known to extend to a depth of 350 m below surface but remains open down dip. The known mineralization extends approximately 2 km along strike and approximately 1 km in the down dip direction to the southwest. The overall morphology of the stratiform mineralized banded iron formation at Pegmont is a flat, gently easterly dipping sheet. In contrast to the almandine garnet in the hangingwall and footwall, the garnet in the BIF is manganiferous spessartite, reflecting the higher whole rock MnO content of the BIF. In fresh rocks, the main sulphide minerals are galena, sphalerite, with subordinate pyrrhotite, pyrite and chalcopyrite. Bedding is typically on a scale of 1 to 5 mm. Apatite, gahnite, and graphite are common minor minerals. The BIF’s consists of banded quartzmagnetite-fayalite-garnet- grunerite-hedenbergite-sulphide. Lead-zinc mineralization at Pegmont is contained within BIF's. The Yellow Water Hole Granite, also part of the Williams Batholith, approximately 18 km from Pegmont, is dated at 1493☘ Ma, postdating main tectonism that affected the sequence. The Squirrel Hills Granite is a non-foliated, porphyritic granite, composed of biotite and hornblende with coarse K feldspar. The southern contact is inferred from airborne magnetics. Present as several low outcrops of tors exhibiting spheroidal and onion skin weathering. It has intruded the project sequence in the northern boundary of the Pegmont lease. The Squirrel Hills Granite, part of the Williams Batholith, is over 100 km north-south and up to 25 km wide. Drill data density in the Lease Amphibolite is less than the mineralization. The southeast edge of Zone 3 is defined where the amphibolite intersects the Lens B BIF, to the southeast of this the Lease Amphibolite is below the BIF's and to the northwest it is above the BIF's. The Lease Amphibolite displays textural zoning, which may reflect chilled margins and compositional layering. Stage 2 quartz ± chlorite ± calcite ± ferroan dolomite ± hematite ± sulphide veins are associated with fine-grained muscovite (illite-phengite) + chlorite ± carbonate alteration.Ī largest amphibolite (hornblende-plagioclase) body is poorly exposed in sub-crop on the edge of the mining lease, called the “Lease Amphibolite”, it is a flay lying, highly continuous body that transgresses the BIF without any apparent displacement. ![]() Stage 1 veins typically are composed of quartz ± K feldspar ± tourmaline ± biotite ± rutile ± ilmenite associated with K feldspar ± muscovite ± tourmaline, or biotite ± muscovite ± garnet alteration. Williams et al identified two stages of alteration. Pegmont is enveloped by a variable but large volume of late or postorogenic fracture/vein- controlled alteration. It is considered to be an example of a BHT deposit. The Pegmont lead-zinc deposit is a body of stratiform lead-zinc sulphides contained within a metamorphosed silicate facies BIF.
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