HIGH GRADE ORE BROKEN, ON SURFACE: GReat Northern, CIRCA 1910
The Great Northern Stockpile is a small stockpile that was not subjected to any systematic sampling prior to 2014. Excavation has shown that the source of the material is from an adit located 30-40 m to the northeast of the stockpile that was exposed in the summer of 2014, and is inaccessible owing to collapsed timbers and infilling with sediment.
The Great Northern stockpile has a distinctive inverted “V”-shape in plan view. The apex of the “V” points north, towards the Great Northern adit. The two legs of the “V” represent the two lobes of the Great Northern dump. The Great Northern stockpile contains an estimate 497 m3 of stockpiled ore. A total of 48 survey stations were completed on the Great Northern Stockpile, and differential GPS measurements were taken of each of the stations. Great Northern stockpile ore will not be processed as part of the bulk sample, but the polymetallic ore from this area is very similar to Broadview and True Fissure, meaning that the Great Northern stockpile will be a low cost, high grade mine target when Thor goes into full-scale production.
Three dimensional model of the Great Northern Stockpile looking north. The adit is located at the top side of the image, and it can be clearly shown that the west dump was used for "ore", and the east side was used to dump the waste rock and separate it from the ore.
The Great Northern Stockpile is one of three existing piles of high-grade ore found at Thor that was sampled and surveyed in 2014.