Tag Archives: Moose Mountain Technical Services

Ausenco to run with Marathon at Valentine gold project

Marathon Gold has appointed Ausenco Engineering Canada as the lead consultant for the prefeasibility study (PFS) on the Valentine gold project in Newfoundland and Labrador, Canada.

As lead consultant in the PFS, Ausenco will undertake a tradeoff study designed to assess the optimum scope, value, and execution strategy for the project, and will incorporate an updated production schedule, facilities design, operating and capital cost estimates, and process design based on ongoing metallurgical studies.

Ausenco will be assisted by Moose Mountain Technical Services in the areas of mineral reserve estimation and mine design. The PFS will also incorporate the results of work currently being conducted at the Valentine project by Terrane Geoscience Inc in the area of geotechnical drilling and pit slope design, by Gemtec for hydrogeology, by Stantec for environmental assessment, and John T Boyd Company for an updated mineral resource estimate.

An October 2018 preliminary economic assessment on Marathon showed the project to be amenable to open pit mining and conventional milling over a 12-year mine life. Average annual production was pegged at 225,100 oz at an all-in sustaining cost of $666/oz. Total mineral resources currently comprise 16.6 Mt of material at a grade of 2.18 g/t containing 1.17 Moz gold in the measured category, 28.5 Mt at 1.66 g/t containing 1.52 Moz of gold in the indicated category, and 26.9 Mt at 1.77 g/t containing 1.53 Moz of gold in the inferred category.

Matt Manson, Marathon President and CEO, said of the news: “Ausenco’s Canadian based engineering team has a broad range of mine development expertise well suited to the Valentine gold project. In particular, they bring the most recent direct experience in the development of a large open-pit gold project in the Maritimes as the engineering, procurement and construction contractor at the successful Moose River gold mine (pictured) developed by Atlantic Gold Corp (now St Barbara Ltd).

“They will join an existing team of specialised sub-contractors already working with Marathon’s owner’s team to develop the best overall project configuration for subsequent feasibility study, permitting and financing.”

The PFS is expected to take around six months to complete, with results expected early in the June quarter of 2020.

XRT ore sorting stacks up for Almaden Minerals at Ixtaca silver-gold project

Almaden Minerals is moving forward with plans to introduce X-ray Transmission (XRT) ore sorting to its Ixtaca silver-gold project in Mexico, with the latest economic study showing the technology can boost production and returns.

The Vancouver-based company previously said conventional XRT ore sorting technology could, among other things, push the average annual metal production above the 147,900 oz/y of gold-equivalent production number set in the prefeasibility study.

The latest study, carried out by Moose Mountain Technical Services, has done that, with the conventional open-pit mine slated to produce 173,000 oz of gold-equivalent output at an all-in sustaining cost of $850/oz over an 11-year life.

Initial capital was pegged at $174 million with a post-tax net present value (5% discount) of $310 million based on gold and silver prices of $1,275/oz and $17/oz, respectively.

Almaden said pre-concentration will use XRT ore sorting to produce a total of 48 Mt of mill feed averaging 0.77 g/t Au and 47.9 g/t Ag. This compares with 73.1 Mt of run-of-mine feed averaging 0.59 g/t Au and 36.3 g/t Ag. Test work had previously indicated ore sorting could separate barren or low-grade limestone host rock encountered within the vein swarm from vein and veined material, Almaden said.

This will see product from the secondary crusher screened in to coarse (+20 mm), mid-size (12 to 20 mm), and fine (-12 mm) fractions, Almaden said, adding coarse and mid-size ore would be sorted by an XRT ore sort machine to eject waste rock. Fine ore will bypass the ore sorter and go directly to the mill.

In addition to this measure, the company plans to use an ore control system during mining. This is “planned to provide field control for the loading equipment to selectively mine ore grade material separately from the waste”, Almaden said.

And, its water and waste management plans include the use of dry-stack tailings at the project, which would include co-disposal of waste with filtered tailings, use much less water than traditional slurry facilities, reduce the mine footprint, allow for better dust control and enable earlier rehabilitation of the tailings and waste disposal areas, Almaden said.