Mariana Minerals

Engineering Technician

Mariana Minerals · San Francisco, CA
San Francisco, CA Closed
Applications are closed for this role. It was originally posted 2026-06-16. It’s no longer accepting applicants — see roles Mariana Minerals is still hiring for →, or browse the live openings below.
Type
Full-time

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.

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