The Buchans-Mary March Project is located in central Newfoundland, 20 km northeast of, and within the same geological group that hosts the former producing Buchans Mine. The Buchans deposits rank as the world’s highest grade polymetallic (Zn-Pb-Cu-Au-Ag) VMS deposits with a Zn equivalent grade of 48%* (produced 16.2 Mt @ 14.51% Zn, 7.56% Pb, 1.33% Cu, 126 gpt Ag and 1.37 gpt Au). Compared to other major VMS camps worldwide, it has seen only modest exploration and research, especially in the past 25 years, and most of the work preceded a new recognition of the geological model.
* Calculated using Zn=$1.00, Pb=$0.85, Cu=$2.25, Ag=$20, Au=$1300
The SE corner of the region also hosted Teck Resources Limited’s Duck Pond Mine, which operated between 2007 and 2015 with an initial reserve of 4.1 Mt averaging approximately 3.3% Cu, 5.7% Zn, 59 gpt Ag and 0.86 gpt Au. The Duck Pond 1,800 tpd flotation mill currently on care/maintenance.
The Buchans-Mary March Project is comprised of several contiguous properties, totaling approximately 39,000 hectares of highly prospective land. Surrounding the historic Buchans Mine property, the land package encompasses the majority of the Buchans belt.
Mary March Property
The Mary March property, comprised of 92 staked claims, 5 licenses, 1 lease and 2 patented lots, totaling 4,129 hectares, is a JV property with Glencore. Canstar is the majority JV partner (56%/44%) and operator and has first right-of-refusal to acquire the remaining interest from Glencore.
Discovery holes drilled at Mary March by Phelps Dodge in 1999 and 2000 produced some of the highest-grade base and precious metal intersections ever achieved in the area outside the Buchans mine. The Buchans mine produced 16.2 million tonnes averaging 14.50% Zn, 7.56% Pb, 1.33% Cu, 126 g/t Ag and 1.37 g/t Au over its 56-year mine life. By comparison, the discovery holes drilled at Mary March by Phelps include;
- Hole MM294-7 returned 10.1% Zn, 1.8% Pb, 0.64% Cu, 122 gpt Ag, and 4.2 gpt Au over 9.63 m;
- Hole MM294-11 returned 16.8% Zn, 5.44% Pb, 0.18% Cu, 660 gpt Ag and 12.2 gpt Au over 0.91m;
- Hole MM294-3 returned 3.02% Zn, 1.08% Pb, 0.13% Cu and 72 gpt Ag over 20.6m.
The Nancy April deposit lies approximately 500 meters west of the Mary March deposit and was discovered in 1999 by Phelps Dodge. The discovery hole intersected 6.8 metres of 1.5% zinc, 0.8% copper and 0.6% lead. In September 2014, the existence of a continuous stockwork zone formed by hydrothermal processes that are conducive to the development of volcanogenic massive sulphide (VMS) deposits was confirmed. Results from a September 2014 drill program included:
- Hole MM14-33 intersected 5.33 meters 1.2% copper, 0.2% zinc, 4.9 gpt silver, 0.4 gpt gold from 66.5 to 71.8 metres, including an interval of 2.3 metres grading 2.5% copper, 0.1% zinc, 8.6 gpt silver and 0.7 gpt gold nested in the above intercept from 69.5 to 71.8 metres.
- Hole MM14-33 returned 93.7 metres of 1.0% zinc, 0.2% lead, and 2.9 gpt silver in stockwork sulphides, including an interval of 10.2 metres of 3.4% zinc, 0.1% copper, 7.1 gpt silver and 0.3 gpt gold.
In early 2019, Canstar undertook a drill program (“Phase I”) consisting of 1,901 metres in five drill holes as well as downhole EM surveys on three of the five holes. The goal of Phase I was to test the mineralized horizon at the top of the extensively altered Mary March panel and included a deep hole (MM-19-36) measuring 538.8 metres testing underneath historical drill hole MM-294-7 as well as testing the Mary March horizon to the southwest which has seen little historic drilling.
While Phase I did not return any VMS, it provided valuable information on structure and alteration in the Mary March area which will help target the next phase of exploration. Strongly altered felsic rocks of the Mary March Panel were encountered in drill holes MM-19-36, 37, 38, and 40. Drill holes MM-19-37 and MM-19-38 also sampled low grade mineralization in the Nancy April footwall which is also a target for future exploration.
Canstar undertook a thorough review of new and historical data related to the Mary March Property during the first half of 2019 leading to a program of prospecting, soil sampling and trenching during the summer of 2019. As part of this program, Canstar discovered a new zone of massive sulphide mineralization at surface approximately 1.8 km along trend from the Mary March discovery hole (MM-294-7). Grab samples from this new zone returned:
- 1.2 g/t Au, 29.4 g/t Ag, and 5.7% Cu (sample 18305)
- 1.5 g/t Au, 54.2 g/t Ag, and 2.3% Cu (sample 18328)
- 2.0 g/t Au, 23.5 g/t Ag, and 1.1% Cu (sample 18303)
Canstar plans to undertake further geochemical and geophysical studies in late 2019 at this new discovery in order to better refine targets for subsequent drilling.
The Buchans Property, acquired through the RTO transaction with Adventus Zinc in June 2018, is comprised of ~22786 Ha and encompasses the historical Buchans Mine and the Mary March/Nancy April properties.
An EM survey was completed in 2017, developing 35 drill-ready targets. Canstar is planning a field program at the Buchans property for the summer of 2019 consisting of prospecting, trenching and ground based geophysicas in order to prioritize targets for a planned drill program in the fall of 2019.
Maps & Figures