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 RoleMariana Minerals is looking for a highly motivated Mechanical Engineer to join our San Francisco Pilot Plant team. You will support the design, installation, and maintenance of first-of-its-kind refining processes for critical minerals. This position plays a critical role in bridging R&D and Operations, ensuring our equipment and work processes are robust, safe, cost-effective, and suitable for commercial production.
What You'll DoDrive design, fabrication, installation, modification, startup, and commissioning of new equipment and pilot plant systems.
Troubleshoot mechanical issues and implement practical solutions to maintain safe, reliable, and efficient plant operations.
Work closely with process engineers and R&D scientists to translate process requirements into equipment modifications, mechanical designs, and plant improvements.
Create and maintain engineering documentation, including P&IDs, process and control narratives, equipment specifications, drawings, CAD models, and equipment manuals.
Identify opportunities to improve equipment reliability, maintainability, and operational performance
Support the development of software and to help drive rapid equipment design, plant reliability, and safe operation
Travel to Mariana sites to support new projects, start-up/commissioning, and troubleshooting initiatives
B.S., M.S., or PhD in Mechanical Engineering or a related field
Experience in automated manufacturing, operations, process scale-up, or plant design in minerals processing, chemicals, specialty materials, oil & gas, or related industries
Demonstrated experience driving equipment design, commissioning, operations, and reliability
Ability to wear multiple hats and take on additional scope in areas such as process engineering, operations, maintenance, and project execution
Strong troubleshooting and problem-solving skills in hands-on plant environments
Strong commitment to Health, Safety, and Environmental compliance and mechanical integrity standards
Excellent technical writing, communication, and teamwork skills
Comfortable working in fast-paced environments and managing ambiguity
Everyone Gets Home Safe. We never put speed or cost ahead of people.
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!
Skills Required
- B.S., M.S., or PhD in Mechanical Engineering or a related field
- Experience in automated manufacturing, operations, process scale-up, or plant design in minerals processing, chemicals, specialty materials, oil and gas, or related industries
- Demonstrated experience driving equipment design, commissioning, operations, and reliability
- Ability to support process engineering, operations, maintenance, and project execution
- Strong troubleshooting and problem-solving skills in hands-on plant environments
- Commitment to Health, Safety, and Environmental compliance and mechanical integrity standards
- Excellent technical writing, communication, and teamwork skills
- Comfort working in fast-paced environments and managing ambiguity
What We Do
Mariana Minerals is a software-first, vertically integrated minerals company focused on supplying critical materials for energy, AI, and defense technologies. It combines digital infrastructure with mineral project development to secure reliable and sustainable supply chains.
