Tracker - July 5, 2022: Spec Value Rating for Endurance Gold Corp
Endurance Gold Corp reported final results on June 28, 2022 for the RC drill program completed on the Eagle Zone this spring at the Reliance gold project in southwestern British Columbia. The company also mentioned that it has completed 5 holes representing 1,109 m of the 8,000 m core program now underway. No details about the core holes were provided other than that they are located in the 020 Zone area which is that part of the Eagle Zone where hole 21-020 last year indicated that the shallow 35 degree southwest dip of the Eagle Zone appears to have flexed and gone sub-vertical. This was the part of the 300 m wide NW-SE trending Royal-Treasure shear corridor previously called Eagle South. The RC holes were too shallow to tell us much about the vertical extent of the 020 Zone, but hole RC 22-078 which yielded 30.48 m of 3.89 g/t gold is at the southeastern limit of the now 400 m long Eagle Zone. The core holes are now testing the vertical extent of the 200 m long 020 Zone. The other important hole in the final RC results is RC22-079 which yielded 10.66 m of 8.57 g/t gold. This hole was spotted north of the 020 Zone and drilled in a NEE direction. It confirms that the shallow SW dipping Eagle Zone continues to be present and well mineralized at the southeastern limit of the drilling within what is now a 1.5 km trend.
If we assume a 400 m long by 100 m wide by 10 m thick dimension for this mineralized slab, at 2.6 specific gravity we get a tonnage footprint of 1,040,000 tonnes. This represents about 167,000 oz gold for each 5 g/t grade so it is fair to say that Endurance has outlined a 150,000-300,000 oz medium grade resource. How the Eagle zone behaves down the hill within the 300 m segment before the Imperial zone starts (ie Crown and Merit) remains to be seen, but the direction for expansion is up the hill in a southeast direction.
The soil sampling shows a gold geochemical anomaly marching uphill which is best explained by gold in bedrock along strike. But even if we double this strike to 800 m we only expand the resource potential into the 300,000-600,000 oz range. The market has hesitated to treat Reliance as an emerging discovery because it has viewed the corridor and the shallow dip of the Eagle Zone as a tonnage constraint. But with the 020 Zone emerging as a potential sub-vertical feeder we are getting close to a perceptual tipping point.
Endurance limits its diagrams to what its exploration work has established, which means there is no graphical depiction of the vision CEO Robert Boyd has about what is unfolding within this corridor of intense iron carbonate alteration. What he imagines for this epizonal orogenic gold system is that fluids traveling up several thousand metres within this structural corridor would have also branched off into any sub-horizontal "openings" that the shearing caused. These are called "Riedel dilation structures" and they are great places for gold to drop out of solution. To make it easier to understand the model I have created a cartoon of the conceptual model and juxtaposed it with a section of the Eagle Zone where the 020 Zone begins. So far Endurance's diagrams are restricted to the portion I have highlighted with a red box. When you limit your back of the napkin tonnage calculations to that portion of the Reliance project, it is hard to get excited. But what if the 020 Zone is more than 1,000 m deep, and has multiple Eagle Zone type slabs branching off it? Obviously the reality of mother nature will have created a much messier geometry. But once Endurance starts chasing the 020 Zone down dip, likely drilling it from the east, it will intersect any such rungs branching off the feeder. The upside for the Reliance play resides not just in a vertical slab striking 800 m and extending 1,000 m deep with an average thickness of 10 m (21 million tonnes with 3.4 million oz for every 5 g/t gold grade), but also for multiple Eagle Zone slabs.
The 8,000 m drill program now underway is cautiously probing the vertical extent of the 020 Zone. The company is not taking arsenic readings of the core with an XRF unit because that is not reliable as it is with sample bags of RC chips, so we will be flying in the dark until assays start arriving, which may not be until August. But by the time Endurance has assays it will have a lot more core holes with logged geology revealing the geometry of the mineralized system within the Royal-Treasure Shear Corridor. Now it is possible everything fades away at depth as it did for Charlie Boitard decades ago with the Imperial Zone. But Boitard did not have a coherent strategy for developing the geology of the system.
When I looked at the longitudinal section for the entire 1.5 km length of the Royal-Treasure Shear Corridor what struck me was that the surface of the Imperial Zone was at an elevation of about 850 m above sea level, but the northeastern limit of the Eagle Zone is at 1,300 m above sea level, a vertical difference of 450 m. When an orogenic gold system is emplaced the fluids tend to travel vertically, branching into any "splays" along the way. I asked Boyd if he knew whether the system is intact in terms of its original vertical orientation, meaning that what is at surface is a product of erosion, or if the region has been tilted so that the surface of the mountain is the same emplacement depth for the entire 1.5 km trend. He said it is impossible to tell at this stage. But if it is vertically intact, one could argue that the Imperial Zone is a deeper feeder portion of the system that has lost 450 m of its vertical extent while up the hill and beyond it remains in place. That raises the question as to how far does the mineralized corridor extend to the southeast up the flank of the mountain? So even while the core rig chases the 020 Zone down dip the company will be extending the road along the strike of the corridor.
Endurance Gold's potential to explode the discovery upside through its 8,000 m drill program is starting to attract an audience, but the breakout will likely not happen until half the program is done and positive assays confirming the vertical nature of the 020 Zone have arrived. But strike extension to the southeast can offset any disappointment in the 020 Zone drilling. Furthermore, in early May Endurance optioned 100% of the Olympic claims from Avino to the northeast where the Kelvin and Olympic showings on the south side of Carpenter Lake (reservoir) were never explored in terms of structural corridors ascending the northern flank of the mountain which is part of the Bendor batholith. The Olympic showings include antimony as does the mineralization at Reliance, evidence that this entire area is much higher in the orogenic system than the quartz vein mineralization of the Bralorne district which produced 4 million plus ounces. Endurance plans soil and biogenic douglas fir needle sampling in this area which highlighted the Royal-Treasure Shear corridor very effectively at Reliance. Land ownership is now at a district scale and by Q1 of 2023 Endurance could have in hand evidence that the emerging gold system at Reliance has one or more structural clones to the northeast. Endurance Gold Corp will remain Bottom-Fish Spec Value rating until the missing piece in the form of demonstrating vertical extent for the 020 Zone is achieved, at which point it will become a Fair or Good Spec Value rated Favorite depending on how aggressively the market has embraced this emerging discovery story.
*JK owns shares in Endurance Gold Corporation