---
title: 'R&D Metallurgist at Mariana Minerals'
canonical: 'https://feeny.ai/job/r-d-metallurgist-mariana-minerals-san-francisco-2y0a92fe9ese'
type: 'job'
last_seen: '2026-09-11'
---

# R&D Metallurgist at Mariana Minerals

- **Company:** Mariana Minerals
- **Location:** San Francisco, CA
- **Compensation:** $110k–$140k
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-09-10
- **Last confirmed live:** 2026-09-11
- **Apply:** https://jobs.ashbyhq.com/marianaminerals/15a2ddc3-c9c1-4d00-abd8-790a2151e8b2

## 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.

## The Role

- The R&D Metallurgist designs, executes, and analyzes experiments to advance Mariana Minerals' hydrometallurgical testing programs. This hands-on laboratory and pilot-scale role focuses on running DOE protocols, operating tank reactors and mining systems, and analyzing data to optimize extraction for critical minerals.

## What You'll Do

- Develop Design of Experiments (DOE) protocols for chemical processing, extraction, and purification
- Analyze metallurgical and process data to identify trends, root causes, and optimization opportunities
- Operate tank reactors, filtration systems, separation equipment, and purification units at bench and pilot scale
- Prepare chemical solutions and reagents according to experimental specifications
- Monitor and control process parameters: temperature, pH, flow rates, residence time, and reagent dosing
- Perform systematic sampling and material handling throughout process streams
- Collect experimental data including process parameters, weights, volumes, and analytical results
- Analyze data using Excel and statistical tools to evaluate performance and identify optimization opportunities
- Generate clear data visualizations, charts, and summary reports
- Maintain detailed laboratory notebooks and digital documentation
- Support DOE planning and multi-variable optimization studies
- Perform routine maintenance, calibration, and troubleshooting of processing equipment
- Follow all chemical handling, PPE, and MSHA/OSHA safety protocols
- Maintain clean, organized, and safe laboratory environments
- Conduct hazard assessments for chemical processes and experimental setups

Desired Qualifications

- Bachelor's degree in Chemistry, Chemical Engineering, Metallurgy, or related technical field preferred
- 5+ years' experience in chemical processing, hydrometallurgy, or laboratory/pilot plant operations
- Experience with Design of Experiments (DOE) methodology and statistical analysis highly desirable
- Hands-on experience with chemical reactors, filtration, and separation equipment
- Advanced Excel proficiency (pivot tables, statistical functions, data visualization)
- Understanding of chemical process fundamentals (mass balance, stoichiometry, reaction kinetics)
- Knowledge of purification techniques (precipitation, solvent extraction, ion exchange, crystallization)
- Ability to read P&IDs and process flow diagrams
- Experience with DOE software (JMP, Minitab, Design-Expert) is a plus
- Exceptional attention to detail and data integrity
- Strong analytical and problem-solving skills
- Excellent communication and documentation abilities
- Self-motivated with ability to manage multiple experiments
- Unwavering commitment to safety and quality
- Valid driver's license required

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)

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