ROOT & CELLAR (Au-Ag, Cu), Newfoundland
Root & Cellar sits within the Avalon Geological Terrane and is primarily being explored for epithermal-type gold-silver mineralization though there are also strong indications and potential for porphyry copper. Porphyry copper and epithermal gold deposits are end members of the same hydrothermal system and so can be found in the same geological setting.
The Property is located near Marystown and Creston on the Burin Peninsula, a three-hour drive from St. John’s.
Root & Cellar hosts several gold occurrences discovered by local prospector, Mr. Jeffery Brushett, over a 5 kilometer strike-length with grades up to 111.5 g/t gold and 1,365 g/t silver. The textures and mineralogy are suggestive of an epithermal system. Two clusters of copper mineralization with grades up to 10.4% copper have also been discovered and may point to a porphyry type mineralization.
Northern Shield has the option to earn a 100$ interest in Root & cellar subject to a 2.5% Net Smelter Return Royalty of which 1% can be bought back by Northern Shield for $1.5M.
The core of the property is dominated by a distinct volcanic sequence, which for its age is relatively pristine, upright and intact. But the geology clearly provides evidence of active and often violent volcanic activity.
At the centre of this volcanic sequence lies the Conquest Zone where modeling of integrated geoscience datasets along with hundreds of gold anomalous to gold-bearing surface samples have outlined a very large epithermal gold-silver system.
Root & Cellar hosts 5 distinct epithermal gold showings and a copper occurrence best exposed in a quarry at Creston. Numerous other gold and copper-bearing samples have been collected through the property.
The gold mineralization is clearly part of an epithermal system with characteristics of low, intermediate and high sulphidation affinity. This is likely the result of the intrusion driving the fluids (and hence the copper porphyry) being telescoped onto the first formed gold mineralization which was likely of low sulphidation affinity.
Recent analysis also strongly suggests the system at Root & Cellar is alkaline related. Alkaline related epithermal gold deposits include Cripple Creek (21 Moz), Colorado, Pogera, Papua New Guinea and Emperor in Fiji.
The five distinct showing at Root & Cellar are:
Drop Zone: with assays to 45.5 g/t Au and 1,365 g/t Ag and characterized by the presence of hessite (a silver telluride).
Hessite (silver telluride)
Conquest: an area now measuring approximately 1,600 x 1,600 meters hundreds of samples assaying greater than 100 ppb Au including channel samples assaying up to 47.9 g/t Au and a recently collected float sample assaying 111.5 g/t Au. Conquest is characterized by high gold to silver ratios.
Windfall; a 200 m wide, gold-bearing fault zone where sampling along a single traverse of the zone identified 29 samples assaying between 0.1 and 17 g/t Au and up to 58 g/t Ag. The discovery was made following up on gold and silver anomalous soil samples collected by Northern Shield in 2020. The mineralization at Windfall is appears to be related to an ENE trending fault zone and is exposed over a 200 metre thickness at this point. The Drop Zone and Braxton-Bradley showings are located along the same structure and have similar geochemical signatures and high silver to gold ratios.
Crustiform banded quartz-carbonate vein - 4.4 g/t Au, 19.5 g/t Ag
Red Rock: up to 2.2 g/t Au hosted in a boulder adjacent to strongly hematized quartz breccia. Such rocks are often observed at the top of low-sulphidation systems.
Braxton-Bradley Zone: possible intermediate-sulphidation setting with deformed silicified hydrothermal breccias and anomalous bedrock gold assays up to 0.9 g/t Au and 2.3 g/t Au in angular samples of float. Other associated assays reported from this zone include 1.8 oz/t Ag (62 g/t Ag) to 4 oz/t Ag (137 g/t Ag), 0.3% Pb, 1.9% Zn, and 1.7% Cu.
Of all the showings, only Bradley-Braxton has seen any exploration prior to Northern Shield optioning the Property. Exploration at Braxton-Bradley culminated in 3 drill-holes to a maximum depth of 50m. All three holes intersected anomalous gold (up to 663 ppb Au).
Creston: up 72 samples collected from Root & Cellar assay > 0.1% Cu with 13 > 1% and, a high of 10.5% Cu. The best copper mineralization is exposed in a quarry at Creston hosted in vent breccias and hydrothermally altered mafic volcanics with 10.5% Cu associated with anomalous Mo, Ag, Zn and Pb and hosted with silicification, epidote and potassium alteration.
Copper porphyries and epithermal gold are end members of the same system.
Modeling of integrated geoscience datasets (IP, Magnetics, geology, geochemistry) along with on-going surface sampling has defined a very large epithermal gold-silver system in the Conquest Zone at Root & Cellar. There are two sub-parallel structural corridors that makeup the Conquest Zone. The Southern Trend is better exposed due to erosional levels whereas the Northern Trend sits underneath the highest topography in the area, so its presence is mostly based on geophysics though edges of the system are exposed on the flanks of the ridge.
Gold was first discovered in the central Conquest area along an east-west trending structure that was hand-grubbed by the prospector with subsequent assays returning 47.9 g/t Au. Further prospecting and sampling have continued to locate gold along this trend including a boulder, largely believed to be in situ, that contains visible gold and assayed 111.5 g/t Au. It was this and other parallel structures that were the focus of the first drill program in 2021 with modest success.
However, knowledge gain from the drill program along with remodeling of the IP concluded with the identification of north-south trending IP anomalies at modest depths. It is believed that the N-S IP anomalies are the principal targets and feeders of the mineralization. These targets are largely capped by a late sequence of bi-modal rhyolitic and basaltic volcanics and sub-volcanic intrusions. For the large part these IP targets do not come to surface except where they intersect the larger east-west structures. It is at these locations that the mineralizing fluids have reached surface and migrated short distances along the east-west structures.
The geological sequence, including the unconformity between the basement andesites and basalts and the overlying late sequence of rhyolite and basalt “cap rock,” is well depicted in sections through the 3D magnetic inversion modelling. Further the near IP anomalies correlate very well with where mineralized fluids have reached surface along the east-west structures that penetrate the cap sequence. The broader and deeper IP anomalies spatially correlate with the level of the unconformity. It is interpreted that the main feeders and hence higher-grade mineralization are to be found be below the unconformity with some fluids expected to have exploited the unconformity to form flat-lying mineralized zones on top of the feeders.
Section through 3D magnetic inversion model with overlaid IP and interpretation. Same section is provided below without overlay for clarity.
The Conquest Zone is interpreted to be a very large alkaline related epithermal gold system.
Potassic altered rhyolite with epidote and specular hematite filling fractures - 0.8 g/t Au
Visible Gold From 30 kilogram boulder form Root & Cellar. A sample from this boulder assayed 111.5 g/t Au. No visible gold was noted in the sample sent for analysis.
Completely silicified mafic volcanic rock containing disseminated sulphides that has subsequently hydrothermally brecciated. Note the ginguro-like rind to some of the fragments. That band contains fine, silvery-bue to greyis-black metallic particles.
Boulder found near the rhyolite dome at the western end of the Conquest Zone. Sample exhibits fragments of strongly acid leached volcanic rock brecciated and cut by chalcedonic quartz veins. Such rocks are indicative above epithermal systems.