About Mariana Minerals

Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We’re reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making.

The Role

Mariana Minerals is looking for a highly motivated Engineering Technician to join the San Francisco Pilot Plant team. You will support the design, deployment, and operation of first-of-its-kind refining processes for critical minerals, while also supporting development of software for automated plant optimization. This position is highly hands-on and will play a critical role in bridging R&D, Process Engineering, and Operations, ensuring processes are robust, safe, cost-effective, and suitable for commercial production.

What You’ll Do

• Support bench-top R&D, pilot-scale experiments, technical evaluations, and other scale-up trials

• Monitor, troubleshoot, and optimize equipment performance.

• Drive evaluations of recovery, throughput, product quality, and equipment reliability.

• Assist with equipment design, installation, commissioning, and modification

• Create SOPs, engineering drawings, and other process design documentation

• Train on all pilot plant operating steps and fill in when needed to help keep pilot plant running to plan

   

Desired Qualifications

• Bachelor’s degree in engineering, materials science, or equivalent field

• 3+ years of hands-on pilot plant, R&D scale-up, or industrial operations experience

• Experience supporting experiments, process trials, or equipment testing

• Ability to collect quality data, document observations, and communicate results clearly

• Experience with process equipment design, procurement, setup, and troubleshooting

• Strong understanding of pH, inorganic chemistry, mass balance, fluid handling, and solid-liquid separation

Our culture is built on three principles:

Extreme Ownership – We take full responsibility for outcomes, relentlessly driving toward solutions.

Engineer Out Requirements, then Automate – We simplify, optimize, and then automate for scale.

Share Your Legos – We collaborate openly, share knowledge, and empower each other to build bigger, better solutions.

Join us as we build the future of responsible mineral sourcing and supply.