Halo Minerals begins trading after £20m AIM float Proactive uses images sourced from Shutterstock

Halo Minerals, a company looking to extract copper from legacy mining waste in northern Chile, has raised £4 million and listed on London's AIM.

The shares started trading on Monday, dropping 2.8% to 17.5p from the 18p issue price of the initial public offering.

At the IPO price, Halo had a market capitalisation of around £20 million.

Operations are focused on processing tailings, the material left behind after ore has been mined and processed, at the Playa Verde project in the Atacama region, the prolific copper-producing area where BHP's Escondida mine is based, along with state-owned giant Codelco that has partnerships with Antofagasta, Freeport-McMoRan and Rio Tinto.

The Playa Verde project holds a JORC-compliant mineral resource of 53 million tonnes at 0.24% copper, with ore reserves of 32.2 million tonnes at 0.25% copper containing an estimated 79,359 tonnes of fine copper.

Based on a copper price of $5.30 per pound, the reserves carry an estimated net present value of $154 million.

The funds raised will be used to advance the project towards a final investment decision, or to a point at which outside project financing becomes available.

Chief executive Andrew Dennan said admission to AIM "represents a significant milestone for Halo", which he said is "well-positioned to support the global transition to sustainable energy through the extraction of critical minerals, delivering both environmental and economic value".

"Listing on AIM strengthens our ability to grow as a company by enhancing our visibility, broadening our shareholder base and providing a platform from which to pursue our long-term strategy."