The Goldboro Project
The Goldboro Gold Project (“Goldboroâ€) is an advanced exploration and development project that forms a strategic part of Anaconda’s strategy for near-term growth. Goldboro is located on tidewater approximately 185 km northeast of Halifax, Nova Scotia within Nova Scotia’s Eastern Goldfields District. Anaconda acquired the project as part of a merger with 100%-owned subsidiary Orex Exploration Inc. in early 2017.
Goldboro Development
Anaconda has been completing geotechnical, hydrogeological, baseline environmental studies and community and aboriginal consultations since acquiring the project. Additionally, Anaconda is currently undertaking a 10,000+ metre infill and exploration diamond drilling program that will continue through Q4 2018.
Anaconda has received permits required to proceed with the extraction of a proposed 10,000-tonne underground bulk sample. In connection with the Bulk Sample, Anaconda has engaged Cementation Canada Inc. ("Cementation") as the mining contractor to assist in the underground development and Bulk Sample extraction. Cementation has mobilized to site and have begun work. The Bulk Sample process is expected to take approximately four months with results to follow thereafter.
The Bulk Sample will provide valuable geological, operational and processing information for design and optimization of the overall project in a feasibility study planned to start in November. Bulk Sample activities will involve site preparation, establishment of safe access underground and extraction of the Bulk Sample, which is expected to be approximately 10,000 tonnes. Extraction of the Bulk Sample will utilize the existing decline developed in the late 1980's with minimal development needed to access mineralized zones and planned mining stopes adjacent to existing workings.
Anaconda have hired local people and contractors to carry out security related duties, surface clearing, transportation and other ancillary activities. In total, including employees of Cementation, approximately 50 people will be working on the Bulk Sample at Goldboro.
Anaconda has also, on August 1, 2018, registered its the Goldboro Project with the Nova Scotia Department of Environment and is currently working on preparing Focus Report which is expected to be submitted early in 2019. The Registration is a significant milestone in the continued development of the Goldboro Gold Project which is scheduled to start pre-production in 2020.
Goldboro PEA
On January 17, 2018 Anaconda announced a positive result of an independent Preliminary Economic Assessment study (“PEAâ€) on the Goldboro Project (see news release dated January 17, 2018). The PEA provides a base case assessment of developing the Goldboro mineral resource by open pit and underground mining, on site concentration through gravity and flotation circuits and leaching of the concentrate and gold recovery at Anaconda’s Pine Cove Mill in Newfoundland.
On October 25, 2018, Anaconda reported updated after-tax economics with respect to the Preliminary Economic Assessment study on Goldboro. The change in after-tax economics reflects the confirmation with the Nova Scotia Department of Natural Resources of the application of a mineral royalty tax of a 1% net smelter return on gold production, which supersedes the higher mineral tax applied in the Previous Report. All dollar amounts are expressed in Canadian dollars unless otherwise noted.
Goldboro Project PEA Highlights*
The base case scenario utilizes a long-term gold price of $1,550 and all dollar figures are presented in Canadian dollars unless otherwise noted. Key assumptions and results from the PEA are summarized below:
* Assumes a 0.77 USD: CAD exchange rate.
** See Non-IFRS Measures below.
The updated Goldboro PEA base case after-tax net present value at a 7% discount rate is $76 million, with an after-tax internal rate of return of 29.3% and pay-back period of 3.3 years. The change in after-tax economics reflects the confirmation with the Nova Scotia Department of Natural Resources of the application of a mineral royalty tax of a 1% net smelter return on gold production, pursuant to Section 121(3) of the Mineral Resources Act and as outlined under Section 71(f) of the Mineral Resources Regulations. This supersedes the higher mineral tax applied in the Previous Report. The base case scenario assumes a long-term gold price of $1,550 per ounce (~US$1,200).
The updated PEA does not incorporate updates to the Mineral Resource as at July 19, 2018. With the increase in Mineral Resources, Anaconda believes there is the potential for increased mine life at the Project and higher potential future mill throughput. The Company is currently preparing to move the Project towards a feasibility study where the newly updated Mineral Resource will be further assessed.
The gold price sensitivity on a pre-tax and after-tax basis as presented in Tables 1 and 2, respectively, demonstrate the significant potential increase in the NPV and IRR of the Project in an increasing gold price environment.
Table 1 – Pre-tax discounted NPV- gold price sensitivity
Pre-Tax NPV* ($M) |
Gold Price (C$ / Ounce) |
|||||
|
|
$1,450 |
$1,500 |
Base Case $1,550 |
$1,600 |
$1,700 |
Discount Rates |
0% |
$152 |
$171 |
$189 |
$208 |
$245 |
5% |
$107 |
$122 |
$137 |
$152 |
$182 |
|
Base Case 7% 7% |
$93 |
$107 |
$120 |
$134 |
$162
|
|
10% |
$74 |
$86 |
$99 |
$111 |
$135 |
|
|
|
|
|
|
|
|
IRR % |
32 |
35 |
38 |
41 2.8 |
47 |
|
Payback – Years |
3.2 |
3.1 |
2.9 |
2.8 |
2.6 |
Table 2 – After-tax discounted NPV- gold price sensitivity
After-Tax NPV* ($M) |
Gold Price (C$ / Ounce) |
|||||
|
|
$1,450 |
$1,500 |
Base Case $1,550 |
$1,600 |
$1,700 |
Discount Rates |
0% |
$101 |
$114 |
$127 |
$140 |
$166 |
5% |
$67 |
$78 |
$88 |
$99 |
$119 |
|
Base Case 7% |
$56 |
$66 |
$76 |
$85 |
$105 |
|
10% |
$42 |
$51 |
$60 |
$68 |
$85 |
|
|
|
|
|
|
|
|
IRR % |
24 |
27 |
29 |
32 |
37 |
|
Payback – Years |
3.6 |
3.4 |
3.3 |
3.1 |
2.9 |
After-tax cash flows reflect a combined Federal and Provincial tax rate of 31% and the Nova Scotia mining royalty tax, which is calculated as a 1% net smelter return on revenue from gold production.
(*) The PEA was prepared in accordance with National Instrument 43-101 (“NI 43-101â€) by WSP Consulting of Toronto, Canada (“WSPâ€). Readers are cautioned that the PEA is preliminary in nature and includes inferred mineral resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves. There is no certainty that results of the PEA will be realized. Mineral resources that are not mineral reserves do not have demonstrated economic viability.
Goldboro Mineral Resource
The Goldboro Mineral Resource was prepared by WSP under the supervision of Todd McCracken, P. Geo., an "Independent Qualified Person", as defined in NI 43-101. The effective date of this Mineral Resource is July 19, 2018 and includes historical diamond drilling as well as 12,356 metres of drilling conducted by Anaconda in the Boston Richardson and East Goldbrook Zones up to June 2018. The recent Mineral Resource Estimate comprises: an open pit resource including 856,300 tonnes of Measured and Indicated Resource at a grade of 3.07 g/t gold (84,500 ounces) and 58,500 tonnes of Inferred Mineral Resource at a grade of 4.10 g/t gold (7,700 ounces); and an underground resource including 2,921,700 tonnes of Measured and Indicated Mineral Resources at a grade of 5.52 g/t gold (518,200 ounces) and 2,067,900 tonnes of Inferred Resource at a grade of 6.70 g/t gold (445,500 ounces).
Highlights of the updated Mineral Resource include:
The following table summarizes the updated Mineral Resource and comparative change from the previous Mineral Resource dated December 31, 2017. The schematic below further illustrates the areas of growth compared to the previous Mineral Resource.
Highlights of the Goldboro Gold Project Mineral Resource Update (effective July 19, 2018):
Category* |
Tonnes (‘000) |
Grade (g/t Au) |
Ounces (Rounded) |
% Change in Grade from Dec 2017** |
% Change in Ounces from Dec 2017** |
Measured |
1,611.8 |
4.23 |
219,300 |
+ 42% |
+ 447% |
Indicated |
2,166.2 |
5.50 |
383,400 |
+ 18% |
(21%) |
Measured and Indicated |
3,778.0 |
4.96 |
602,700 |
+11% |
+15% |
Inferred |
2,126.4 |
6.63 |
453,200 |
+ 56% |
+ 30% |
* Combined Open Pit and Underground Mineral Resources. Open Pit Mineral Resource based on a 0.50 g/t Au cut-off grade; Underground Mineral Resource based on 2.00 g/t Au cut-off grade
** Refer to the Company’s technical report entitled “Goldboro Project Preliminary Economic Assessment†dated March 2, 2018 for further details (the “Previous Reportâ€).
Goldboro Mineral Resource Estimate – Effective July 19, 2018
Resource |
Au Cut-off |
Category |
Tonnes |
Au (g/t) |
Troy Ounces |
Open Pit |
0.50 |
Measured |
608,700 |
2.80 |
54,900 |
Indicated |
247,600 |
3.72 |
29,600 |
||
Measured and Indicated |
856,300 |
3.07 |
84,500 |
||
Inferred |
58,500 |
4.10 |
7,700 |
||
Underground |
2.00 |
Measured |
1,003,100 |
5.10 |
164,400 |
Indicated |
1,918,600 |
5.74 |
353,800 |
||
Measured and Indicated |
2,921,700 |
5.52 |
518,200 |
||
Inferred |
2,067,900 |
6.70 |
445,500 |
||
Combined
|
0.50/2.00 |
Measured |
1,611,800 |
4.23 |
219,300 |
Indicated |
2,166,200 |
5.50 |
383,400 |
||
Measured and Indicated |
3,778,000 |
4.96 |
602,700 |
||
Inferred |
2,126,400 |
6.63 |
453,200 |
Mineral Resource Estimate Notes
1. Mineral Resources were prepared in accordance with NI 43-101 and the CIM Definition Standards (2014). Mineral Resources that are not mineral reserves do not have demonstrated economic viability.
2. Open pit Mineral Resources are reported at a cut-off grade of 0.5 g/t gold that is based on a gold price of CAD$1,550/oz. and a gold processing recovery factor of 95%.
3. Underground Mineral Resource is reported at a cut-off grade of 2.0 g/t gold that is based on a gold price of CAD$1,550/oz. and a gold processing recovery factor of 95%.
4. Appropriate mining costs, processing costs, metal recoveries, and inter ramp pit slope angles were used by WSP to generate the pit shell.
5. Appropriate mining costs, processing costs, metal recoveries and stope dimensions were used by WSP to generate the potential underground resource.
6. Rounding may result in apparent summation differences between tonnes, grade, and contained metal content.
7. Tonnage and grade measurements are in metric units. Contained gold ounces are in troy ounces.
8. Contributing assay composites were capped at 80/g/t Au.
9. A density factor of 2.7g/cm3 was applied to all blocks.
The Mineral Resource is based on validated results of 316 surface drill holes and 119 underground drill holes, for a total of 79,104 metres of diamond drilling that was completed between 1984 and June 2018. The Mineral Resource includes 12,356 metres of drilling conducted by Anaconda up to June 2018, focused exclusively on infill and expansion drilling in the Boston Richardson and East Goldbrook Zones.
Deposit Type and Gold Mineralization
The Goldboro Deposit is a turbidite-hosted orogenic gold deposit hosted within a sequence of alternating argillites and greywacke. These deposit types are typically characterized by the formation of gold bearing quartz veins within the argillite units commonly referred to as belts. The belts are folded into upright anticlines, and gold is deposited, during fold formation. Veins, which form during deformation, form in three major geometries commonly referred to as reefs: saddle reefs, leg reefs and spur reefs. Saddle reefs occur about the apex of the fold and are commonly the dominant vein types within this deposit type such as at the Dufferin deposit. Leg reefs extend down the limbs of the fold, beyond the saddle reef and are generally parallel with the argillite layers. Spur reefs are veins that cross between layers and may be in the apex of the fold or on its limbs.
The Goldboro Deposit contains all three types of reefs outlined above, but is also characterized by mineralization within the argillite that together form belts. Many of the gold deposits in Nova Scotia are sometime referred to as saddle reef deposit; these have gold bearing belts generally restricted to the hinges of the anticlines. Because the Goldboro Deposit contains saddle, leg and spur reefs and has gold within the Argillite hosting the veins, the Goldboro Deposit contains significantly more gold resources than deposits of the similar dimensions that contain gold only in particular types of reefs or only within the quartz veins.
The Goldboro Deposit contains at least 30, stacked, mineralized belts that vary in thickness from less than a meter up to 20 meters. The mineralized belts are folded into a tight, gently east-plunging, anticline referred to as the Upper Seal Harbour Anticline. The deposit is divided into three broad zones: the East Goldbrook, Boston-Richardson, and West Goldbrook Systems. The East Goldbrook and Boston-Richardson systems are separated by a thick (up to 80 metres) greywacke sequence (the Boston-Richardson Marker) with the East Goldbrook System above the greywacke and the Boston Richardson below. The West Goldbrook is separated from the Boston-Richardson by a fault zone but is generally the continuation of the Boston Richardson zone on the west side of the fault. The trace of this Upper Seal Harbour anticline crosses the property and is found near the Dolliver Mountain several kilometers to the west of the Goldboro
Deposit demonstrating that the structure which hosts gold continues for several kilometers.
The Meguma Terrane
The Goldboro Deposit is hosted within the Goldenville Group of rocks within the Meguma Terrane of Nova Scotia. The Goldenville group consists of a sequence of siltstones and sandstones approximately 6.7 km thick. It is separated from the overlying Halifax Group which contains more shale and is 11.8 km thick (Sangster and Smith, 2007). The entire Meguma Terrane is pervasively folded into kilometre-scale, east-west or northeast-southwest trending, upright folds that can be traced for many kilometers across Nova Scotia. The Upper Seal Harbour anticline is one of these folds. At numerous locations in the eastern Meguma Terrane gold deposition is associated with these structures and this forms the Eastern Gold Fields of Nova Scotia.
Gold was discovered in Nova Scotia in 1861 and a reported 1.2 million oz. were mined sporadically from multiple small-scale operations before 1968 (Table 1). This included mining at Goldboro between 1893 to 1912 when approximately 414,887 short tonnes of gold ore was mined at an average grade of 6.7 g/t gold. A total of 54,871 ounces of gold was produced from the Boston-Richardson Mine.
Historic gold production from various districts in Nova Scotia (Sangster and Smith, 2007)
Gold District |
Years Active |
Ounces |
Grams |
Goldenville |
1862-1941 |
209,383 |
6,511,821 |
Caribou |
1869-1968 |
91,336 |
2,840,543 |
Oldham |
1862-1946 |
85,178 |
2,649,020 |
Waverly |
1862-1940 |
72,567 |
2,256,821 |
Montague |
1863-1940 |
65,197 |
2,027,624 |
Upper Seal Harbour |
1893-1958 |
57,846 |
1,799,001 |
Renfrew |
1862-1958 |
51,596 |
1,604,620 |
North Brookfield |
1887-1936 |
43,148 |
1,341,887 |
Wine Harbour |
1862-1939 |
42,347 |
1,316,976 |
Salmon River (Dufferin) |
1881-1939 |
41,805 |
1,300,148 |
Isaacs Harbour |
1862-1958 |
39,694 |
1,234,493 |
Lower Seal Harbour |
1894-1949 |
34,188 |
1,063,253 |
Molega |
1888-1950 |
33,460 |
1,040,612 |
Mount Uniacke |
1867-1941 |
27,737 |
862,621 |
Tangier |
1862-1919 |
26,287 |
817,510 |
Moose River* |
1888-1939 |
25,917 |
806,025 |
Forest Hill |
1895-1957 |
25,102 |
780,685 |
Fifteen Mile Stream |
1879-1941 |
21,220 |
659,930 |
South Uniacke |
1888-1948 |
20,762 |
645,701 |
Lake Catcha |
1887-1961 |
17,962 |
558,603 |
Other |
165,889 |
5,159,154 |
|
Total |
1,198,619 |
37,277,048 |
There is no record of commercial production from the Meguma deposits from the period 1980 to present. Recent “mining†activity in the Meguma since the early 1980s has focused mainly on advanced underground exploration and bulk samples of varying sizes. The largest of these was collected from the Forest Hill deposit with 95,000 tonnes processed at an average grade of 6.7 g/t gold. Recent trial mining is being conducted at the Dufferin Mine and the Moose River mine opened in October of 2017.
Comparison with the Victoria Gold Fields of Australia
The Victoria Gold Fields of Victoria, Australia, have produced tens of millions of ounces of gold since 1851 and the area has striking geological similarities with the Meguma Terrane of Nova Scotia. The Victoria Goldfields are hosted in Cambro-Ordovician sand and siltstones as are the Eastern Goldfield of Nova Scotia. Both areas are deformed into a series of upright to reclined, tight to open folds with variable, but generally shallow, plunges. And both areas are intruded by Devonian intrusions. Gold mineralization occurs in the same structural setting within the folds and have similar styles and associations. The age of mineralization within the Victoria Goldfields is thought to be near 440 Ma and between 376 and 408 Ma within the Eastern Gold District of Nova Scotia. The geological similarities between these two areas are commonly used to indicate the potential for the Meguma Terrane of Nova Scotia to host significantly more gold than has yet to be discovered.
2017 and 2018 Exploration Results
Since the summer 2017, Anaconda has completed a total of 42 diamond drill holes (BR-17-01 to 13 and BR-18-14 to 42) totalling 12,230.6 metres. Drilling has focussed on testing the down plunge, down-dip and along strike extension of the Boston-Richardson (“BRâ€) Gold System and the East Goldbrook (“EGâ€) Gold System. Drilling also focussed on infilling under-drilled areas of the deposit in order to upgrade mineral resources from the inferred to indicated category with focus on sections 9050E, 9100E, 9150E, 9250E, 9350E, 9450E, 9500E, 9550E and 9650E (see plan map and sections below).
Drilling of the first five holes (BR-17-01 to 05; 643 m) was completed in order to collect samples for metallurgical test work on the Goldboro mineralization, with each of the completed holes twinning an historic drill hole.
Highlight assays from the summer 2017 drilling program include:
In addition to the metallurgical drilling program described above, Anaconda completed thirty-seven drill holes on the property (BR-17-06 to BR-17-13 and BR-18-14 to 49) totaling 15,3579 m. Hole locations were selected to provide local infill and mineralized zone extension information. Drilling has been successful in extending the EG and BR Gold Systems along strike to the east and at depth.
Highlight assays to date from the 2018-2017 drilling program include:
Drilling up to and including drill hole BR-18-42 have been incorporated in the most recent NI43-101 Mineral Resource Estimate. Drill holes BR-18-43 to 49 have not been incorporated into mineral resource.
Goldboro Metallurgy
A composite metallurgical sample was collected from all assay samples greater than 0.5 g/t gold from drill holes BR-17-01 to 05. A total 139 samples were used to create a 324 kg composite sample. Preliminary development of a process flowsheet has defined overall gold recoveries in the range of 95.1% to 95.3% by gravity separation, flotation and cyanide leaching of both gravity and flotation concentrates.
The test program and preliminary process design for the recovery of gold was conducted by Thibault & Associates Inc. of Fredericton, New Brunswick. Pre-concentration by gravity separation and flotation was investigated for a potential reduction in throughput tonnage for downstream cyanide leaching. At a grind size of 80% passing 110 micron, the recovery of gold to the gravity concentrate was 46.4% to 62.1% at a concentrate grade of 4,255 g/t Au to 4,587 g/t Au. Flotation of the gravity separation tails using a standard reagent scheme for flotation produced a mass yield of 5.8% to 6.7% at a concentrate grade of 22.3 g/t gold to 24.3 g/t gold. The combined recovery of gold by gravity and flotation pre-concentration was 96.6% to 97.8%.
Gold in the gravity and flotation concentrates was amenable to cyanide leaching. Intensive cyanide leaching tests on gravity concentrates defined a gold extraction of 99.5% over 48 hours. Cyanide leaching of the flotation concentrate had a gold extraction in the range of 96.6% to 97.3% over 48 hours for a regrind of 80% passing 18.1 and 12.8 micron, respectively. The overall gold recovery based on a process flowsheet including gravity, flotation, flotation concentrate regrind, cyanide leach of flotation concentrates and intensive cyanide leaching of gravity concentrates was 95.1% to 95.3%.