Troilus grows indicated resource to 11.2Moz

Troilus said the project, within the Frôtet-Evans Greenstone Belt, is now the second largest undeveloped gold-copper deposit in Canada, where five of the eight largest deposits are in construction.

The measured and indicated resource has more than doubled since the 2020 resource estimate to include an indicated resource of 508.3Mt grading 0.69gpt gold equivalent. The company said new contributors to the open pit resource, accounting for about 28% of the indicated ounces, were the definition at the Southwest Zone and the new discovery of Zone X22.

"When we look at the large developing assets right now … you're seeing a lot of de-risking of these large, low-grade bulk tonnage assets, being de-risked with partnership or alternative financing through partnership," Troilus Gold chief executive Justin Reid told Mining Journal.

Equinox Gold is developing Greenstone with Orion Mine Finance, and IAMGOLD has Sumitomo as a partner as it builds Cote.

A partnership could be the future of Troilus once it completes a feasibility study for a 35,000tpd operation with a more than 20-year mine life towards year-end or in early 2024.

Troilus said more than 99% of the resource within the indicated category is as amenable to open pit mining. This mineralisation is within zones Z87, J, X22, and Southwest, which will form the basis of the feasibility study.

The company anticipates being able to deliver higher-grade material of 1.2gpt gold equivalent during the initial years of a future mining operation, which would kick-start its economics and reduce the pay-back period. 

Troilus comprises four main deposits: X22, J and 87, which will form a super pit, and Southwest. The connector zone between the two is 87 and J where the company intersected 138m, grading almost 1.8gpt. The discovery hole at X22 returned almost 30m grading 4.3gpt, at the surface.

"It's all about how fast you can repay the capital, drop your cutoff grade, and drive the life of pushing grade through. You will see this in our feasibility, where we have four early production sites that are going to feed that higher grade. We are targeting 1.2-1.4gpt through the mill early," said Reid.

Infrastructure

Reid believes the size of the Troilus deposit could sustain a throughput of 50,000-60,000tpd, similar to the Canadian Malartic and Detour mines. However, the company will stick to the 35,000tpd concept to not negate the capital cost savings that benefit the project from not having to develop existing infrastructure.

"We have inherited and significantly upgraded a lot of infrastructure [including a 6.5km2 tailings facility, roads, 171kV power line feeding its 50MW substation]. Looking at the other growth development stories in construction, it is not the fixed-price things blowing up. It's the civils involved in the building of these mines impacting the CAPEX overruns.

We had a replacement cost pre-inflation for infrastructure at US$350 million, and with the inflation hitting everybody today is probably closer to $500 million," said Reid.

Troilus is eight months into permitting, having already filed a detailed project description with the federal and provincial governments. The terms of reference have been negotiated and received, and preliminary consultations are done. It aims to file its environmental impact assessment by mid-2024 and have full permits in place in 2025.

Shares in Troilus Gold opened 10% higher at 44c, valuing the company at C$100 million.