Mariana Minerals, a software-first, vertically integrated critical minerals company, closed a $310 million Series B on August 3 led by Khosla Ventures, with participation from Andreessen Horowitz (a16z), Breakthrough Energy Ventures, Greenoaks, Halo Fund, Pax Ventures, StepStone Group, BHP Ventures, Washington Harbour Partners, and strategic investors including Mitsubishi Corporation and In-Q-Tel. The round brings total funding to approximately $400 million. CEO Turner Caldwell, formerly Tesla senior manager of battery minerals and metals, built Mariana to apply software orchestration and AI to both mining operations and refining, treating each site's operational data as feedback to accelerate the next deployment.
Mariana operates two flagship projects: Copper One in southeastern Utah (acquired late 2025, restarted autonomous mining within 4 months, targeting 50,000 metric tons of refined copper annually) and Lithium One in East Texas (broke ground Q4 2025, world's first GWh-scale facility extracting lithium from oil & gas produced water, commercial production targeted H1 2027). The company's proprietary MarianaOS platform unifies project execution, refinery operations, and mine management into a single AI/ML stack. Khosla quoted that “critical minerals decide whether America builds its own future or depends on China.”
For infrastructure and supply chain architects, Mariana's $310M capital raise signals that venture-backed autonomous mining has reached factory-scale ambitions. AI-driven orchestration claims require validation under actual production stress: Copper One must prove 50k tonne/year throughput with autonomous scheduling, and Lithium One must complete full commercialization by H1 2027. The investor mix—combining climate VC, industrial strategics (BHP), and national-security-adjacent capital (In-Q-Tel)—suggests confidence in supply-chain geopolitics and domestic EV/grid infrastructure demand. Watch output data from both projects to de-risk the execution thesis.