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Granada Project

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Overview

Mine TypeOpen Pit
StagePermitting
Commodities
  • Gold
Mining Method
  • Truck & Shovel / Loader
Mine Life3 years (as of Jan 1, 2014)
SnapshotPermits in place to mine 550 t/day from the open pit (“Rolling Start”) and ship to a local mill; Previous engineering work to be updated towards building a mill on site.

Owners

SourceSource
CompanyInterestOwnership
Gold Bullion Development Corp. 100 % Direct
The Property is 100% owned by Granada Gold (formerly Gold Bullion Development Corp.) and currently comprises two minig leases (BM 813 and BM 852), twenty-four (24) CDC claims, twenty-five (25) CL claims and one CLD claim and covers a total area of 1,468.74 ha (14.69 km2).

Deposit type

  • Vein / narrow vein
  • Mesothermal

Summary:

The Granada property lies within the Abitibi Greenstone Belt, the northern part of the Granada Gold Mine Property is traversed by the Larder Lake-Cadillac fault (“CLLF”). It is a typical example of a large transcrustal fault zone that hosts many world-class mining camps (>100 Mt) such as Val-d’Or, Malartic, Cadillac, Larder Lake, Kirkland Lake, and Matachewan (Poulsen et al., 2000). However, gold deposits are not distributed regularly along the CLLF. Multiple secondary faults at Granada have become areas of intense interest since they may have acted as permeable conduits for mineralizing fluids.

The Granada property is located within intensely hydrothermally altered rocks of the Timiskaming group. The property is underlain principally by east-west trending, north-dipping interbedded polymictic conglomerate, porphyry-pebble conglomerate, greywacke and siltstone-mudstone of the Granada Formation.

The Granada deposit is a quartz-vein mesothermal gold deposit hosted by late Achaean Timiskaming sedimentary rock and younger syenite porphyry dykes dated at 2673+/-3 Ma as per works by Davis in 1991. The dykes belong to a late tectonic alkaline magmatic suite that hosts the mesothermal gold mineralization in the Kirkland Lake and Timmins gold camps in Ontario and in Duparquet, north of Rouyn-Noranda, in the Province of Quebec. The mineralization is mainly confined in the Conglomerate/Greywake package S1 of the Granada formation.

Mineralization spatially associated with syenitic intrusions includes two subtypes: quartz-carbonate veins such as the Granada mine (Couture and Willoughby, 1996), and less common disseminated sulphides enriched in Au and Cu (Couture and Marquis, 1996; Legault and Lalonde, 2009).

Gold mineralization is hosted by east-west trending smokey grey, fractured quartz veins and stringers. Free gold occurs at vein margins or within fractures of the quartz veins or sulphides. Late north-easterly-trending sigmoidal faults also host high-grade gold mineralization. Accessory minerals include tourmaline, carbonate, chlorite, and disseminated sulphides. Pyrite is the dominant sulphide typically occurring within the immediate wall rock to the quartz veins. Minor pyrite does occur within the veins themselves. Additional sulphides such as chalcopyrite, arsenopyrite sphalerite and galena are present in trace amounts. Fuchsite (chromium mica) is present in the immediate wall rock to the quartz veins.

Vein #1
Vein # 1 was the original discovery vein on the Property. It extends for 600 m across the Property. The vein’s width can vary from greater than 1 m to a couple of centimetres. Gold grades are very erratic from nil to greater than 100 g/t Au. Shaft #1 was sunk to exploit this vein during the underground operations of 1930-1935. The vein only contributed to approximately 5% of the gold production during this period due to the vein’s erratic grade. The vein was later the target of open pit operations by KWG Resources during 1993 and 1994.

Vein #2
Vein #2 is more correctly described as a mineralized zone of two parallel quartz veins, one in the hanging wall and the other in the footwall, separated by a zone of millimetre-scale quartz veinlets in altered conglomerate. The two main veins are lenticular, locally greater than 1 m in width with metre-scale portions thinning to several centimetres. The hanging wall vein is generally thicker, more continuous and of higher grade (6 to 10 g/t Au) than the footwall vein. The hanging wall vein, plus associated veinlets and pyritic alteration haloes average 3 m in thickness. The intervening zone of quartz veinlets averages 5 m in width and is locally auriferous in the order of 0.7 to 0.8 g/t Au. The footwall vein is generally boudinaged with associated veinlets and pyritic alteration haloes averaging 2 m in thickness yielding on average assay grades of 4 to 5 g/t Au. The entire vein #2 zone averages 10 m in width averaging 3.5 to 4 g/t Au. This vein system was the principal sources of ore for the historical underground operations and open pit production for KWG Resources. The bulk of the historical underground production came from this zone. The heterogeneous distribution of gold grade along strike within the Vein #2 zone resulted in the selective mining of the zone from two shallow pits by RSW-BÉROMA in the year 2000. A western extension of the #2 zone was partially drilled and defined by KWG Resources in 1995 with the proposed pit referred to as 2B. RSWBÉROMA calculated a non-NI 43-101 compliant geological resource of 28,501 tonnes at 2.4 g/t Au (Trudel, 2000).

Vein #3
Vein # 3 was discovered during underground exploration by KWG Resources while drifting on the fifth level between Vein #1 and #2. It is described as a large shear zone containing numerous quartz veinlets hosting free gold.

Vein #5
Vein #5 is the most continuous vein of the Granada property. It has been traced by drill holes from surface to the seventh level of the mine (213 m vertical). It is hosted within the conglomerate along the northern contact with a porphyritic syenite sill. On surface, trench samples of Vein #5 yielded weakly anomalous assays of 0.51 g/t Au over 15 m. Underground development reported visible gold when the vein was encountered.

Vein A & B
Both Veins A and B were discovered after underground operation ceased. Little descriptive information is available for these zones. Vein A outcrops on surface just east of the waste rock pile at 900E and 425N in a trench.

Reserves at June 23, 2022

Pit constrained mineral resources are reported at a cut-off grade of 0.55 g/t Au within a conceptual pit shell.
Underground mineral resources are reported at a cut-off grade of 2.5 g/t Au within reasonably mineable volumes.
CategoryOre TypeTonnage CommodityGradeContained Metal
Measured In-Situ (OP) 4,840,000 t Gold 1.68 g/t 261,000 oz
Measured In-Situ (UG) 60,000 t Gold 3.84 g/t 8,000 oz
Measured Total 4,900,000 t Gold 1.7 g/t 269,000 oz
Indicated In-Situ (OP) 2,440,000 t Gold 2.09 g/t 164,000 oz
Indicated In-Situ (UG) 870,000 t Gold 3.93 g/t 110,000 oz
Indicated Total 3,320,000 t Gold 2.57 g/t 274,000 oz
Measured & Indicated In-Situ (OP) 7,280,000 t Gold 1.81 g/t 425,000 oz
Measured & Indicated In-Situ (UG) 940,000 t Gold 3.92 g/t 118,000 oz
Measured & Indicated Total 8,220,000 t Gold 2.05 g/t 543,000 oz
Inferred In-Situ (OP) 420,000 t Gold 1.78 g/t 24,000 oz
Inferred In-Situ (UG) 2,590,000 t Gold 5.19 g/t 431,000 oz
Inferred Total 3,010,000 t Gold 4.71 g/t 456,000 oz

Mining Methods

  • Truck & Shovel / Loader

Summary:

The current report presents the scenario of Phase I – Open Pit with custom milling to IamGold Westwood (former Doyon) mill in Abitibi. The scenario schedules to produce 550 tpd of ore over 3 years which should be hauled to the Iamgold mill and process in batches.

The mining of Granada deposit will follow the standard practice of an open-pit operation with the conventional drill and blast, load and haul cycle, using a drill / truck / excavator mining fleet, and supported by a fleet of auxiliary equipment. The run-of-mine (RoM) will be drilled, blasted and loaded by hydraulic excavators and delivered by trucks to an ore stockpiling area.

The ore will then be loaded onto transport trucks and delivered to the Iamgold processing plant, approximately 43 km from the mine site while the waste rock material will be hauled to the waste disposal areas near the pits or backfilled into the mined pits.

During this study, SGS came to the conclusion that the riskier item associated to mining is the control of the mining dilution during the operations. The ore zones are relatively thin following a 45-55 degrees dip and are favorable to an important dilution. In this study, SGS estimated the dilution to 25% at a gold grade of 0.00 g/t. Based on our experience and on similar operations, these estimates are judged acceptable but a considerable effort will be required during the operations to achieve these values. The effect of an increase in mining dilution is to lower the average mill feed grade and directly affect the project profitability. As is can be seen in the sensitivity analysis, the overall project profitability is extremely sensitive to the mill feed grade. SGS recommends to pursue the analysis of calculating the mining dilution during a feasibility study by considering various approaches such as lower the height of the benches in ore material, do in-fill drilling, increase the assaying of the ore zones, control and follow the ore blasts movements, etc.

The previously PEA Technical Report (2013) was based on the assumptions that the Granada gold deposit could be put in production at a rate of 7,500 tonnes per day over a period of 11years. An on-site concentrator with gravity-cyanidation processing was included in the economic study.

Production was to come from an open pit designed to supply 6,500 tonnes per day (tpd) and an underground (U/G) mine supplying 1,000 tpd. The underground operation was planned to operate from a main ramp only, avoiding the cost of sinking a shaft. Two mining methods were proposed for the UG production, both as variants of the Cut-and Fill methods.

Comminution

Crushers and Mills

TypeModelSizePowerQuantity
Jaw crusher 1.07m x 1.22m 1
SAG mill 2700 HP 1
Ball mill 1000 HP 1

Summary:

The ore having an average grade of 4.24 g/t will be hauled by trucks on a distance of approximately 43 km from the Granada mine to IMG and discharged on a dedicated pad nearby the crusher house. When convenient, the ore will be dumped directly on the 27” aperture crusher hopper grizzly by the incoming trucks. If not, the ore will be retrieved from the pad and delivered to the surface crusher with a front end loader. Oversize will be left aside or break with the existing hydraulic rock breaker. Crushing is done with a 1.07 m x 1.22 m jaw crusher and the crushed ore is conveyed to the two 2,800 tonne mill ore bins.

Grinding of the Granada ore will be done using the 2,700 HP SAG mill in close circuit with a primary battery of 500 mm hydrocyclones. Cyclones overflow feeds a 1,000 HP ball mill in close circuit with a secondary battery of 600 mm hydrocyclones. Because of the smaller size of the Knelson concentrator (30”), it is possible that only a portion of the secondary hydrocyclones underflow will pass by the gravity separator to be followed by a Gemini shaking table. The other portion, or the whole gravity separator tailings, as the case may be, will report to the 1,000 HP ball mill. The gravity circuit concentrate will go directly to the refinery. Secondary cyclone overflow reports by gravity to the 27 m leaching thickener.

Processing

  • Gravity separation
  • Shaker table
  • Carbon re-activation kiln
  • Smelting
  • Electric furnace
  • Flotation
  • Agitated tank (VAT) leaching
  • Carbon in leach (CIL)
  • Carbon in pulp (CIP)
  • Carbon adsorption-desorption-recovery (ADR)
  • Solvent Extraction & Electrowinning
  • Cyanide (reagent)

Summary:

At least for some time, all ore from the Gold Bullion project will be processed in batches at the Iamgold Doyon mill (IMG). The mill originally built in the 1970’s was completely refurbished between 2011 and 2013 in order to efficiently process the Westwood ore.

The actual scenario for Gold Bullion (GBB) is to mine by open pit between 175,000 and 200,000 tonnes of ore per year at a rate of 550 tonnes per day and have the ore processed at IMG. The IMG mill has ample capacity to process some 2,420 tonnes of ore from the Westwood Mine every day. But for the first two years, due to mine development, the ore from the Westwood Mine will be processed at a rate of only 600,000 tpy or some 2,380 tpd, five days per week. Subsequently, the tonnage will eventually increase gradually to reach the annual nominal capacity of 850,000 tpy at the beginning of the fourth year. In the mean time the Gold Bullion ore will permit to close part of the gap between the Westwood Mine throughput and the IMG mill nominal capacity of 3,200 tpd.

The original scenario between GBB and IMG was in line with 50,000 tonne batches, every 63 to 64 days IMG would stop milling the Westwood ore for a period of 15 days and will process the GBB ore at a rate of 2400 tpd, 24 hours per day, 7 days per week. To ensure that the IMG mill never runs short of ore during the 15 days allotted to GBB, the mill will stop processing the Westwood ore only when at least 30,000 tonnes of the GBB ore will be stockpiled at Doyon and another 20,000 tonnes stockpiled at Granada.

The existing leaching circuit remained the same as it was when Doyon was processing its own ore. The circuit has a 60-hour retention time at the mill nominal feed rate of 3,200 tpd. Since the Granada ore needs only 48 hours to get +95% gold dissolution, in order not to over cyanide and risking to reprecipitate the gold in the in the last leaching tanks, tanks 155 and 160 may be bypassed. The circuit will thus comprise 5 primary and 2 secondary CIL tanks followed by 5 CIP tanks. Loaded carbon is screened and reports to the loaded carbon tank. Leaching tails undergo the cyanide destruction circuit.

The carbon elution – refining circuit comprises mainly a loaded carbon tank, an acid wash tank, a carbon strip vessel, a bank of electrowinning cells and an induction furnace. Stripped carbon is reactivated in a horizontal kiln, quenched and classified. Classifier oversize is ready to be reused while very fine carbon particles are filtered in a filter press and sent to the Xstrata Horne smelter.

The tailings from the CIP circuit will be treated in the mill SO2-AIR cyanide destruction plant to eliminate the cyanide. The cyanide destruction circuit comprises mainly two 250 m3 reactors in parallel in which SO2 is added probably on the form of sodium bisulphite. Air is injected to the reactors with a blower. If needed, some lime and copper sulfate could be added to the reactors.

If required by IMG, prior to be sent to the tailings ponds the mill tailings will be desulfurized. Main desulfurization machinery includes two 2.8 m x 3 m conditioners, one 20 m3 rougher unit cell and 2 banks of four DR-180 scavenger flotation cells. Concentrate will be pumped to the Westwood 20 m paste backfill thickener while the desulfurization tailings will report to the main tailings pond.

The flotation (desulfurization) tailings will be pumped to the tailings pond 3 West and allowed to settle. Supernatant water will then be pumped to the polishing pond 3 East. Clear water from the polishing pond will finally be pumped to the process water reservoir.

Based on previous metallurgical testing it is probable that 50% of the gold will be recovered at the gravity circuit and out of the remaining 50%, another 90% will be recovered from the leaching of the gravity tailings for a total gold recovery of 95%.

Recoveries & Grades:

CommodityParameterAvg. LOM
Gold Recovery Rate, % 95
Gold Head Grade, g/t 4.24

Production

CommodityUnitsLOM
Gold oz 73,585
All production numbers are expressed as metal in doré.

Production Costs

CommodityUnitsEstimated
Cash costs Gold CAD 885 / oz *  CAD
Assumed price Gold CAD 1,400 / oz *  CAD
* According to 2014 study / presentation.

Project Costs

MetricsUnitsLOM Total
Initial CapEx $M CAD 2
Sustaining CapEx $M CAD 2.9
Closure costs $M CAD 1.2
Total CapEx $M CAD 6.7
OP OpEx $M CAD 32.6
Total OpEx $M CAD 65.1
Total Taxes $M CAD 5.7
Royalty payments $M CAD 3.1
Gross revenue (LOM) $M CAD 102.7
Pre-tax Cash Flow (LOM) $M CAD 28.4
After-tax Cash Flow (LOM) $M CAD 22.7
Pre-tax NPV @ 6% $M CAD 24.7
After-tax NPV @ 6% $M CAD 19.5
Pre-tax IRR, % 169.4
After-tax IRR, % 136
Pre-tax payback period, years 0.5
After-tax payback period, years 0.7

Required Heavy Mobile Equipment

Ref. Date: December 31, 2014

SourceSource
HME TypeModelSizeQuantityLeased or
Contractor
Bulldozer Caterpillar D6 1 Leased
Drill (blasthole) Atlas Copco AC-ROC D55152 1 Leased
Excavator Volvo 460 2 Leased
Excavator Caterpillar 336 1 Leased
Grader Caterpillar 12M 1 Leased
Loader Caterpillar 980H 1 Leased
Truck (haul) Volvo A35C 35 t 7 Leased
Truck (water) 5000 gallons 1 Leased

Personnel

Mine Management

Job TitleNamePhoneEmailProfileRef. Date
President and CEO Frank J. Basa 819-797-4144 fbasa@granadagoldmine.com LinkedIn Dec 30, 2023

Total WorkforceYear
67 2014

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