Overview
Status | Closing / Closed |
Mine Type | Underground |
Commodities |
|
Mining Method |
- Transverse open stoping
- Longitudinal retreat
- Cemented backfill
|
Processing |
- Gravity separation
- Concentrate leach
- Carbon in leach (CIL)
- Cyanide (reagent)
|
Mine Life | 2018 |
Mining operations at Lapa continued through year-end 2017 with ore being stockpiled for processing in 2018. Once production from Lapa mine is completed later in 2018, official reclamation and restoration work will begin, with full closure anticipated in 2026–2027. |
Summary:
The Lapa property is located near the southern boundary of the Archean-age (2.7 billion years old) Abitibi Subprovince and the Pontiac Subprovince within the Superior Province of the Canadian Shield. The most important regional structure is the Cadillac-Larder Lake (CLL) fault zone marking the contact between the Abitibi and Pontiac Subprovinces. The fault zone passes through the property from west to east, and is marked by schists and mafic to ultramafic volcanic flows that comprise the Piché group (up to approximately 300 metres thick in the mine area). On the Lapa property, the fault zone displays a "Z" shaped fold to which all of the lithologic groups in the region conform. Feldspathic dykes cut the Piché group, especially near the fold. North of the Piché group lies the Cadillac sedimentary group, which consists of 500 metres or more of well-banded wacke, conglomerate and siltstone with intercalations of iron formation. The Pontiac group sedimentary rocks (up to approximately 300 metres thick) that occur to the south of the Piché group are similar to the Cadillac group but do not contain conglomerate nor iron formation.
All of the known gold mineralization along the CLL fault zone is epigenetic (late) vein type, controlled by the structure. The mineralization is associated with the fault zone and occurs within or immediately adjacent to the Piché group rocks.
The Lapa deposit is comprised of the Contact Zone and five satellite zones. The Contact Zone accounts for approximately 60% of the mineral reserves.
The ore zones are made up of multiple quartz veins and veinlets, often smoky and anastomosing, within a sheared and altered envelope containing minor sulphides and visible gold. The Contact Zone is generally located at the contact between the Piché group and the Cadillac group. The satellite zones are located within the Piché group at a distance varying from ten to 50 metres from the contact with the Cadillac group, except for the satellite zones 7 and 8 at 150 metres from this same contact, and the Contact North Zone, which is located approximately ten metres north of the Contact Zone within the Cadillac group. The sheared envelope consists of millimetre-thick foliation bands of biotite or sericite with silica and, in places, cuts across rock units. Quartz veins and millimetre-sized veinlets parallel to the foliation account for 5% to 25% of the mineralization. Visible gold is common in the veins and veinlets but can also be found in the altered host rock. Sulphides account for 1% to 3% of the mineralization; the most common sulphides, in order of decreasing importance, are arsenopyrite, pyrite, pyrrhotite and stibnite. Graphite is also rarely observed as inclusions in smoky quartz veins.
The Contact and satellite zones are tabular mineralized envelopes oriented east-west and dipping very steeply to the north, turning south at depth. The economic portion of the zone has been traced from depths of approximately 450 metres to more than 1,500 metres below the surface. The Contact Zone has an average strike length of 300 metres, varies in thickness from 2.8 to 5.0 metres and is open at depth. Locally, some thicker intervals have been intersected but their continuity has not been demonstrated. The satellite zones have thicknesses similar to the Contact Zone.
Mining Methods
- Transverse open stoping
- Longitudinal retreat
- Cemented backfill
Summary:
Lapa hosts an underground mining operation accessed by a 1,369-metre-deep shaft. Two mining methods are used – longitudinal retreat with cemented backfill, and locally transverse open stoping with cemented backfill. The dilution rate for mining the reserves averages 71%. The production rate has risen to 1,700 tonnes per day.
Processing
- Gravity separation
- Concentrate leach
- Carbon in leach (CIL)
- Cyanide (reagent)
Source:
Summary:
Excavated ore is trucked to a dedicated Lapa plant at the LaRonde processing facility with grinding, gravity and leaching circuits. The Lapa facility consistently operates above its design rate of 1,500 tonnes per day. Concentrates from Lapa’s gravity and leach circuits are sent to the LaRonde refinery to produce doré bars.
Recoveries & Grades:
Commodity | Parameter | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 |
Gold
|
Recovery Rate, %
| ......  | ......  | ......  | ......  | ......  | | |
Gold
|
Head Grade, g/t
| 4.24 | 4.24 | 4.64 | 5.83 | 5.59 | 6.06 | 6.48 |
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Production:
Commodity | Units | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 |
Gold
|
oz
| ......  | 34,026 | 48,410 | 73,930 | 90,967 | 92,622 | 100,730 |
Silver
|
oz
| ......  | ......  | | | | | |
All production numbers are expressed as payable metal.
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Operational Metrics:
Metrics | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 |
Tonnes milled
| 311,013 t | 398,248 t | 592,683 t | 559,926 t | 638,800 t | 640,422 t |
Daily milling rate
| | 1,090 t | 1,619 t | 1,534 t | 1,750 t | |
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Reserves at December 31, 2017:
Category | Tonnage | Commodity | Grade | Contained Metal |
Proven
|
127 kt
|
Gold
|
3.75 g/t
|
15 koz
|
Proven & Probable
|
127 kt
|
Gold
|
3.75 g/t
|
15 koz
|
Measured
|
159 kt
|
Gold
|
3.62 g/t
|
18 koz
|
Indicated
|
576 kt
|
Gold
|
4.07 g/t
|
75 koz
|
Measured & Indicated
|
734 kt
|
Gold
|
3.97 g/t
|
94 koz
|
Inferred
|
587 kt
|
Gold
|
7.16 g/t
|
135 koz
|
Commodity Production Costs:
| Commodity | Units | 2018 | 2017 | 2016 | 2015 | 2014 |
Credits (by-product)
|
Gold
|
USD
|
-1 / oz
|
-2 / oz
|
|
-1 / oz
|
|
Cash costs
|
Gold
|
USD
|
819 / oz
|
801 / oz
|
717 / oz
|
578 / oz
|
659 / oz
|
Total cash costs
|
Gold
|
USD
|
873 / oz
|
757 / oz
|
732 / oz
|
591 / oz
|
667 / oz
|
Total cash costs
|
Gold
|
USD
|
872 / oz†
|
755 / oz†
|
732 / oz†
|
590 / oz†
|
667 / oz†
|
† Net of By-Product.
Operating Costs:
| Units | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 |
Total operating costs ($/t milled)
|
CAD
| 123 | 120 | 121 | 117 | 107 | 110 |
Financials:
| Units | 2018 | 2017 | 2016 | 2015 | 2014 |
Capital expenditures
|
M USD
| | |
|
6.49
|
20.2
|
Revenue
|
M USD
| 39.8 | 64.6 |
92.2
|
104.78
|
115.25
|
Gross profit
|
M USD
| 11.7 | 24.1 |
8.27
|
21.3
|
28.2
|
Corporate Filings & Presentations:
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Aerial view:
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