Name of the Project
Colosseum gold and rare earths project.

Location
San Bernardino County, California, in the US, in the Clark Mountain/Walker Lane area and within the Mojave National Preserve.

Project Owner/s
Mining and exploration company Dateline Resources.

Project Description
The project is a proposed restart of the former Colosseum gold mine, which produced about 344 000 oz of gold before mining ceased in 1992 and stockpile processing ended in 1993. The historical operation comprised the North and South openpits and a carbon-in-pulp plant, which has since been removed.

The May 2026 bankable feasibility study (BFS) outlines a conventional openpit, truck-and-shovel operation feeding a two-million-tonne-a-year carbon-in-leach processing plant. The plan is based on total ore mined of 20.6-million tonnes grading 0.95 g/t gold, average metallurgical recovery of 91% and total net gold production of 573 000 oz over a 10.4-year production life. Average production over the first six years is estimated at 75 400 oz/y.

The project has a Joint Ore Reserves Committee 2012 mineral resource of 44.5-million tonnes grading 0.76 g/t gold for 1.08-million ounces using a 0.25 g/t cutoff. The BFS also reports a maiden ore reserve of 20.6-million tonnes grading 0.95 g/t gold for 630 000 oz. The broader Colosseum project also has rare earths exploration potential. 

Potential Job Creation
The BFS estimates maximum construction site manning at about 200 personnel. The mining workforce is estimated at 223 in Year 0, peaking at 329 in Year 1, before being reduced to 57 during the later stockpile-processing years.

Net Present Value/Internal Rate of Return
At a base case gold price of $4 200/oz, the BFS estimates a pretax net present value (NPV), at a 5% discount rate, of $785-million and a pretax internal rate of return (IRR) of 49.5%. The after-tax NPV is estimated at $551-million, with an after-tax IRR of 38.6% and a three-year after-tax payback. At a spot gold price of $4 700/oz, the project’s pretax NPV increases to $999-million and its pretax IRR to 59.5%.

Capital Expenditure
The BFS estimates preproduction capital expenditure of $249-million, including $16-million of capitalised mining, plus a $25-million contingency.

Latest Developments
Financing discussions are advanced, while preconstruction activities have started ahead of a final investment decision.

The access road has been rehabilitated, a laydown and storage property has been optioned, and historical foundations from the former processing plant have been uncovered and assessed for potential reuse. Long-lead procurement is also being progressed through the front-end engineering design (FEED) phase.

Key Contracts, Suppliers and Consultants
GR Engineering Services (FEED for the processing plant); AMDAD (mining input and ore reserve estimate); H&S Consultants (mineral resource estimate); Agapito Associates and Tundra Resource Analytics (BFS inputs contribution); and Alvarez & Marsal (contracting strategy and site construction management support).

Contact Details for Project Information
Dateline Resources, tel +61 2 9375 2353 or email info@datelineresources.com.au.