4/19/21 | 500 Foot Level
On March 31st and April 2nd of 2021, 9 channel samples were cut from the remaining accessible areas with visible vein in the back/rib of the 500-level east drift (east of the Bates-Hunter shaft). Two additional channel samples were taken from the back of the closest stope to the Becker-Bates shaft where two previous grab samples assayed at 5.95 and 11.7 opt of gold. Channel samples were cut utilizing a battery-powered angle grinder, chiseled out and collected into sealable sample bags. One grab sample of the muck being removed from the 730-level sump was dried and sent for assay as well.
Samples were cut and collected where vein was visible and accessible, heading east from the 500 -level station towards the Becker-Bates shaft. An approximate spacing of six feet between channels was established; however, due to faulting and overhead lagging from stopes, there are sections where samples could not be taken. A majority of the channels were taken from the back, whilst some were upper rib channels due either to deviation of the vein or the drift being originally driven off-vein. The 2 channel samples in the stope preceded the blasting of a bulk sample (~1.5 tons) and give insight into the potential grade of the material.
The samples were sent to Hazen Research, Inc. in Golden, Colorado on April 12th, 2021 for fire assay analysis with gravimetric finish. Results of the analyses were received April 19th, 2021 and are presented in Table 1, from Analytical Report 21M01656.
BH500E Sample Descriptions
All cut samples are 1-inch wide, 0.75-inch deep, over a reported length (unless otherwise stated)
FG stands for fault gouge: physically ground-up material infilling a cross-cutting fault of the vein
RS stands for “Rainbow Stope”, the stope closest to the Becker-Bates Shaft on the 500 Level
SM stands for Sump Muck from the 730 level
Black coating seen on the vein has been interpreted as a manganese oxide coating most likely caused by years of submersion in water
Euhedral crystals are those that are well-formed, with sharp, easily recognized faces/form
Subhedral crystals are those having a partial or incomplete crystal face or form
Anhedral crystals are those that have poor to no form and no recognizable crystal faces
QSP is the abbreviation for Quartz-Sericite-Pyrite
BH500E-003.5-FG: 15-inch channel of the fault gouge of a fault cross-cutting the main vein and offsetting the vein. Mostly QSP alteration material with some slight mineralization seen including peacocking chalcopyrite.
BH500E-014: 20-inch rib-cut channel of sulfide vein mineralization with a majority of subhedral to euhedral pyrite with needle-like crystals of quartz and some slight chalcanthite mineralization. A black oxide coats the pyrite.
BH500E-015: 18-inch rib-cut channel of sulfide vein mineralization with a majority of subhedral to euhedral pyrite with needle-like crystals of quartz and some slight chalcanthite mineralization. A black oxide coats the pyrite.
BH500E-016: 24-inch rib-cut channel of sulfide vein mineralization with a majority of anhedral to subhedral pyrite, amorphous quartz and some slight chalcanthite mineralization
BH500E-017: 10-inch, extra-wide channel of sulfide vein mineralization measuring 2.5 inches in width.
BH500E-018: 17-inch channel of sulfide vein mineralization measuring 1 inch in width with abundant disseminated pyrite in the alteration surrounding the vein.
BH500E-019: 9-inch rib-cut channel of a sulfide vein mineralization measuring 5.5 inches in width with mostly fine-grained anhedral pyrite and substantial amorphous quartz at vein split.
BH500E-020: 10-inch rib-cut channel of sulfide vein mineralization measuring 7.5 inches in width with mostly fine-grained anhedral pyrite and substantial amorphous quartz.
BH500E-021: 9-inch channel of sulfide vein mineralization measuring 8 inches in width with mostly fine-grained anhedral pyrite and substantial amorphous quartz.
BH500E-RS1: 11.5-inch channel of sulfide vein mineralization measuring 8 inches with a majority of peacocking chalcopyrite, dark grey galena with interpreted copper sulfosalts, and anhedral pyrite.
BH500E-RS2: 15-inch channel of sulfide vein mineralization measuring 8 inches with a majority of peacocking chalcopyrite, dark grey galena with interpreted copper sulfosalts, and anhedral pyrite. Additionally, a 2-inch-wide stringer occurs, displaying subhedral pyrites and little to no base metal mineralization.
BH730-SM: (GRAB) Approximately 18 oz (volume) of the sump muck from about 6-8 feet below the 730 level, consisting of a sandy-silt material and watery-slime. No mineralization visible.
Observations, Interpretations and Continuing Work
Visual identification of rock carrying significant grades of gold will be critical for future mine development, grade control, and production. Through the 500E Channel Sampling, one emerging interpretation is that when the vein is composed of more fine-grained anhedral pyrite and amorphous quartz, higher grades are seen in comparison to that of veins composed of more well-formed, euhedral pyrite and needle-like quartz crystals. More channel sampling on other levels will help refine this interpretation. A more definite interpretation so far is that a vein consisting of more base-metal sulfides, such as chalcopyrite and galena, carries substantially higher grades. Lastly, the material being removed from the sump below the 730 level appears to carry a low, yet significant quantity of gold; naturally, since the material will be processed through the mill regardless, gold will be recovered. Continuing geologic work will consist of core drilling on the 240 level, mapping the veins and structural geology of the 500E drift and the 240 level, and continued sampling as mine rehabilitation progresses.