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.

Position Summary

Join our analytical lab in San Francisco as an Analytical Lab Chemist. You’ll run sample prep and analytical testing on state-of-the-art equipment in a newly renovated lab, keep data accurate and instruments performing at their best, and dig into problems that don’t come with a textbook answer, like an unknown sample straight from the plant. You’ll work closely with our lab technicians and learn alongside an analytical team that supports labs across multiple sites, with room to grow into owning the lab or a regional or global role as we expand.

Responsibilities

• Perform precise sample preparation across various matrices, including weighing, digestion, dilution, and filtration

• Prepare standards and calibration solutions

• Operate, calibrate, and troubleshoot analytical equipment, particularly ion chromatography (IC), ICP-OES, ICP-MS, and XRF

• Record data accurately in LIMS or lab notebooks and review results for integrity

• Help diagnose analytical problems, including unknown samples from the plant, and work with operations on next steps

• Write and improve SOPs and lab workflows

• Support lab technicians and share knowledge across the team

• Follow all SOPs, chemical hygiene plans, and PPE requirements; manage chemical inventory and waste to regulatory standards

Qualifications & Experience

• Bachelor’s degree in Chemistry, Chemical Engineering, or a related field

• Lab experience through undergraduate research, internships, co-ops, or work

• Hands-on ion chromatography (IC) experience strongly preferred

• Solid wet chemistry skills, including acid digestion and preparing standards

• Experience with ICP-OES/MS, XRF, AA, GC, HPLC, or UV-Vis, whether in research or coursework

• A troubleshooter who likes figuring out why an instrument or result isn’t right

• Familiarity with EPA, ISO, or GLP/GMP standards a plus

• Mining, metals, or hydrometallurgy exposure a plus

• Authorized to work in the US without sponsorship

Schedule

• Full-time, salaried

• 25–35% travel (about one week a month) to our other lab sites, including occasional weekend travel

Working Environment & Physical Requirements

• Regular work with chemicals, acids, and acid digestions; standard lab PPE required (safety glasses, lab coat, gloves)

• Able to stand and work at a lab bench for extended periods and lift samples and supplies up to 25 lbs

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!