Overview
Stage | Pre-Feasibility |
Mine Type | Open Pit |
Commodities |
|
Mining Method |
|
Mine Life | 10 years (as of Jan 1, 2022) |
The completion of pre-feasibility study for the Robertson open pit project at Cortez, was significant contributors to reserve growth. As a result, Robertson’s maiden Barrick's attributable proven and probable gold reserves are estimated at 1.0 million ounces at 0.46g/t. |
Source:
p. 81
Robertson mine Project is a part of Cortez Complex.
Barrick is the operator of the joint venture and owns 61.5%, with Newmont Corporation owning the remaining 38.5%.
Contractors
- Subscription is required.
Summary:
The deposit is about 2285 m long, 910 m wide, and approximately 400 m thick. The deposit has been drill tested to about 420 m depth.
Robertson is an igneous related gold system. Gold mineralization is found in Upper Plate siliciclastics of the Devonian Slaven and Silurian Elder formations, as well as inside Eocene intermediate composition igneous rocks, primarily diorite and granodiorite. Mineralization is primarily concentrated around the Tenabo Stock in three main areas: Gold Pan in the northwest, Porphyry in the east to northeast, and Altenburg Hill in the southeast. Gold mineralization overprints an initial contact metamorphic hornfels event and a subsequent chalcopyrite– pyrrhotite–pyrite–chlorite–actinolite skarn event.
A series of later-staged phyllic and propylitic alterations are present, primarily altering later faults, fractures and late-stage feldspar porphyry dykes.
Mineralization at Gold Pan can be separated into two zones: Gold Pan and 39A, which represent one gold depositional event but in two different host lithologies in the Slaven Formation. Mineralization at Gold Pan is controlled by a gently northeast-dipping metabasalt strata, which is preferentially altered to a biotite hornfels, with skarn alteration overprinting the hornfels. Mineralization at 39A is controlled by the 39A structure, a bedding sub-parallel thrust that is also gently northeast dipping. The 39A structure is preferentially skarn-altered, with gold most strongly present at and under the ........
Summary:
Robertson is proposed to be in alignment with Cortez open pit operations using conventional truck and shovels with conventional drill and blast techniques followed by load and haul. Material will be drilled and blasted on 12 m and mined on 12 m benches.
Flow Sheet:
ROM ore is dumped into the crusher dump pocket at the mill and discharges onto a vibrating grizzly. Grizzly oversize material is crushed in a jaw crusher. Grizzly undersize material and the jaw crusher discharge are conveyed to the coarse ore stockpile. The coarse ore is conveyed to the SAG mill and lime is added to the belt based on ore requirements. The grinding circuit includes one SAG mill and one ball mill. Discharge from the SAG mill is screened on one of two vibrating screens.
Screen oversize is conveyed to a cone crusher where it is crushed prior to being recycled to the SAG mill feed. Screen undersize and ball mill discharge flow by gravity to the hydrocyclone feed pump box. The slurry is pumped from the pump box to the hydrocyclones. The ball mill is operated in closed circuit with the hydrocyclones to produce the target grind size for the CIL circuit, which is nominally 150 µm. The underflow from the hydrocyclones is recycled to the ball mill feed; the overflow from the hydrocyclones discharges into an agitated surge tank, which feeds the grind thickener.
Flow Sheet:
Summary:
- subscription is required.
Reserves at December 31, 2022:
Category | Tonnage | Commodity | Grade | Contained Metal |
Proven & Probable
|
23 Mt
|
Gold
|
0.46 g/t
|
1.63 M oz
|
Corporate Filings & Presentations:
- Subscription is required.
- Subscription is required.