--- title: 'Materials Engineer at Mariana Minerals' canonical: 'https://feeny.ai/job/materials-engineer-mariana-minerals-san-francisco-4jx4x8mbzr79' type: 'job' last_seen: '2026-09-11' --- # Materials Engineer at Mariana Minerals - **Company:** Mariana Minerals - **Location:** San Francisco, CA - **Compensation:** $100k–$140k - **Employment:** full-time - **Work type:** onsite - **Posted:** 2026-08-05 - **Last confirmed live:** 2026-09-11 - **Apply:** https://jobs.ashbyhq.com/marianaminerals/11b76624-5564-42a4-820b-16cc09563ff9 ## Job description ## 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. ## Role Overview Mariana Minerals is seeking a highly motivated Materials Engineer to join our R&D and product development team. The successful candidate will be responsible for designing, developing, and optimizing processes for novel material synthesis - from lab-scale proof-of-concept to pilot and commercial scale implementation. This position will play a critical role in translating laboratory discoveries into scalable, economically viable production processes. ## What You’ll Do - Conduct lab-scale and pilot scale wet chemical synthetic experiments to validate proof-of-concept ideas and develop new material formulations. - Design and execute experiments to establish reaction parameters, yield optimization, and reproducibility. - Evaluate and select equipment and process configurations for pilot-scale and commercial-scale operations. - Develop process flow diagrams (PFDs), process and instrumentation diagrams (P&IDs), and mass/energy balances. - Collaborate with multidisciplinary teams including R&D scientists, operations, and external vendors to ensure smooth scale-up. - Support process safety reviews, risk assessments, and environmental compliance planning. - Collect and analyze process data to identify areas for optimization, cost reduction, and performance improvement. - Prepare technical documentation, reports, and presentations for internal and external stakeholders. - Work closely with cross-functional teams including lab technicians, pilot plant engineers, process engineers, project execution teams, and more to scale designs from lab through to commercial scale - Work closely with the software and machine learning teams to automate capital project execution workflows and develop reactor and plant optimization algorithms ## What You’ll Bring - MS degree in Materials Science, Chemistry, Materials Engineering, or Chemical Engineering (PhD preferred). - Hands-on experience in materials synthesis (e.g., solid-state, hydrothermal, precipitation, or other chemical synthesis techniques). - Proficiency with materials characterization tools such as XRD, SEM, TEM, BET, TGA/DSC, and spectroscopic methods. - Experience with process design, equipment specification, and scale-up of laboratory processes to pilot or production scale. - Strong analytical and problem-solving skills with a data-driven approach. - Excellent communication and teamwork skills in a multidisciplinary environment. - Familiarity with process simulation tools (e.g., OLI systems or equivalent) is a plus. Our culture is built on four principles: 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! ## About Mariana Minerals ## Company Overview - **One-liner**: Mariana Minerals is a software-first, vertically integrated minerals company focused on supplying the minerals critical to modern energy, AI, and defense technologies. - **Entity Type**: Private (Series A, $85M funding in July 2025) - **Headquarters**: San Francisco, California, United States - **Founded**: Not publicly available - **Founders**: Turner Caldwell (Co-Founder & CEO) ## Core Business - **Primary industry**: Metal Ore Mining / Critical Minerals - **Target customers**: B2B – energy, AI, and defense supply chains (including downstream manufacturers and government entities) - **Mission or purpose**: "Create a future of critical mineral abundance" by reimagining the global minerals supply chain with software, automation, and data-driven decision making. ## Products & Services - **Copper One (formerly Lisbon Valley Copper Mine)**: World’s first autonomous mine, located in Utah. Produces copper using integrated automation and software control. Restarted production in April 2026. - **Lithium One**: Lithium project (on the roadmap or early development). - **Other mineral projects**: Graphite, Uranium, Rare Earth Metals, Cobalt, Nickel, Aluminium – at various stages (stealth or roadmap). - **CapitalProjectOS**: Internal software platform for capital project management (mentioned in leadership bio). - **Technology Stack**: React, dbt, TypeScript, Python, TensorFlow, PyTorch, microservices, SCADA, Autodesk, and many others – indicating a strong software engineering backbone. ## Market Standing - **Valuation/Market Cap**: Not disclosed (private company) - **Key Metric**: Total funding – $85M Series A (July 2025, 1 investor) - **Notable Investors/Partners**: Lead investor not publicly disclosed (Andreessen Horowitz was pitched but not confirmed as an investor). Partners include Bot Auto, WeRide, Pronto, Atoms (based on LinkedIn mentions). Also works with UMA (Utah Mining Association). - **Growth Signals**: Headcount grew 3,575% YoY to 107 employees (as of mid-2026). 73 active job postings. Opened the world’s first autonomous mine (Copper One) in April/May 2026, generating significant industry news and social media engagement. ## Competitive Advantages - **Software-first approach**: The company builds automation and data systems from the ground up, rather than layering tech onto legacy mining operations. This enables fully autonomous mining. - **Vertical integration**: They develop, own, and operate mineral projects, controlling the entire value chain from extraction to processing. - **Deep tech stack**: Use of AI/ML (TensorFlow, PyTorch), simulation, and real-time control systems to optimize mining operations. - **First-mover in autonomous mining**: Copper One is claimed to be the world’s first autonomous mine, giving them a significant lead in operational efficiency and safety. ## Strategic Focus - Scale autonomous mining operations beyond copper (lithium, graphite, uranium, etc.) - Secure domestic supply of critical minerals for U.S. energy, AI, and defense needs. - Continue aggressive hiring across engineering, operations, and field roles. - Expand from Utah to additional sites (Houston engineering office, potential new projects). ## Why Work Here - **Culture principles**: "Extreme Ownership", "Engineer Out Requirements, Then Automate", "Share Your Legos" – emphasizing accountability, simplification, and collaboration. - **Work environment**: High-growth startup with a mission-driven focus on critical infrastructure. Offices in San Francisco (HQ), Houston (Engineering), and La Sal, Utah (mine site). Hybrid/remote policy not explicitly stated, but multiple office locations suggest flexibility for field vs. office roles. - **Notable perks**: Opportunity to work on cutting-edge autonomous systems and AI in a traditional industry. Strong engineering culture with modern tech stack (React, Python, ML). Rapid career growth due to company expansion. - **Talent sources**: Attracts talent from Tesla, Redwood Materials, Lilac, ExxonMobil, Amazon Web Services, and other tech/energy companies – indicating a high-caliber peer group. ## Sources 1. [marianaminerals.com](https://marianaminerals.com/) 2. [marianaminerals.com/careers](https://marianaminerals.com/careers) 3. [marianaminerals.com/about](https://marianaminerals.com/about) 4. [jobs.ashbyhq.com/marianaminerals](https://jobs.ashbyhq.com/marianaminerals) 5. [linkedin.com/company/mariana-minerals](https://www.linkedin.com/company/mariana-minerals) ## Other roles at Mariana Minerals - [Sr./Staff Process Engineer - Detailed Engineering and Plant Design](https://feeny.ai/job/sr-staff-process-engineer-detailed-engineering-and-plant-design-mariana-m9xewg6hdcc5) — Houston, TX - [Industrial Electrician](https://feeny.ai/job/industrial-electrician-mariana-minerals-moab-snerjqgb4qbh) — Moab, UT - [Sr. Technical Recruiter](https://feeny.ai/job/sr-technical-recruiter-mariana-minerals-san-francisco-hr9b2676c4vw) — San Francisco, CA - [R&D Metallurgist](https://feeny.ai/job/r-d-metallurgist-mariana-minerals-san-francisco-2y0a92fe9ese) — San Francisco, CA - [Maintenance Mechanic](https://feeny.ai/job/maintenance-mechanic-mariana-minerals-moab-bc9jcgbeg61b) — Moab, UT - [Process Maintenance Technician](https://feeny.ai/job/process-maintenance-technician-mariana-minerals-moab-c6pyeb53jmef) — Moab, UT - [Mobile Maintenance Supervisor](https://feeny.ai/job/mobile-maintenance-supervisor-mariana-minerals-moab-0zyyzma9tm1n) — Moab, UT - [Sr./Staff Pyrometallurgical Process Engineer](https://feeny.ai/job/sr-staff-pyrometallurgical-process-engineer-mariana-minerals-houston-dpv5c9qyznbb) — Houston, TX - [Electrician](https://feeny.ai/job/electrician-mariana-minerals-east-50vs2farzxq5) — East, TX - [Staff Process Controls Engineer - Networking and Systems Administration](https://feeny.ai/job/staff-process-controls-engineer-networking-and-systems-administration-mariana-yysg2twzjx6r) — San Francisco, CA