An environmentally friendly alternative to cyanide-based leaching, 3D imaging and virtual reality are among the finalists of Goldcorp’s Disrupt Mining challenge, announced Monday.

Acoustic Zoom, EnviroLeach Technologies, LlamaZOO Interactive, and Open Mineral AG have been selected to take part in the “Shark Tank”-style event on March 4 during the annual PDAC convention in Toronto. The finalists can receive an up to $1 million investment.

The purpose of the event, Goldcorp CEO Todd White said in a press release, is to discover “revolutionary” new technologies that could change the mining industry.

Acoustic Zoom, a 2017 semi-finalist, proposes to use high-frequency 3D borehole seismic imaging to map subsurface geological structures with what it calls “unprecedented resolution,”  in order to make mineral exploration both faster and more cost effective.

EnviroLeach Technologies has developed an “eco-friendly” extraction process that it says is a viable alternative to the acid- and cyanide-based leaching currently used to extract precious metals. Cyanide is cheap and effective, but its high toxicity presents a danger to the environment and can have a catastrophic effect on aquatic life in the event of a spill.

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EnviroLeach’s solution will be able to process a high volume of materials using a formula based on five FDA-approved ingredients, and will provide “similar or superior leach kinetics and recoveries” to cyanide. While acid- and cyanide-based leaching consume themselves during the process, EnviroLeach’s solution is recyclable, CEO Duane Nelson told CIM Magazine last August.

LlamaZOO wants to use its MineLife VR virtual reality software platform to map mine plans onto a life-sized interactive experience that will aid companies in all facets of mine development, including resource management, mine planning and reclamation. The company is also part of the Digital Technology Supercluster, which recently received federal funding.

Open Mineral AG proposes digitizing the physical commodity trading process by using cloud-based solutions to eliminate the role of the middleman and allows companies to work directly with buyers. The company was founded by former Glencore executives.

The finalists will be judged by Integra Resources president and CEO George Salamis, McEwen Mining chief owner Rob McEwen, Goldcorp director and Softtek president Blanca Treviño, University of British Columbia mining engineering student Veronica Knott, and Chrysalix Venture Capital president and CEO Wal van Lierop.

Eight semi-finalists will present their solutions at the Disrupt Mining innovation expo prior to the event.