5E Advanced Materials is a development-stage mining and materials company focused on building a domestic boron production facility at its Fort Cady Project — a colemanite borate deposit in the Mojave Desert near Newberry Springs, California. 5E plans to extract boron using in-situ leaching (ISL), injecting a weak hydrochloric acid solution underground to dissolve the ore, then pumping the leach solution to the surface for processing into boric acid. Boric acid is an industrial material used in specialty glass, fiberglass insulation, ceramics, fertilizers, and defense applications, and is also an input into advanced boron derivatives used in EVs, semiconductors, and clean energy. 5E currently operates a small-scale facility producing roughly one short ton per day of boric acid, primarily to qualify product with potential customers and gather engineering data. About 14 to 15 customers across 8 market segments have qualified 5E's boric acid, though the company has no binding supply agreements yet. The planned Phase 1 commercial facility targets 130,000 short tons per year of boric acid, with first production targeted in the second half of 2028, a total capital cost of ~$435M, and an all-in sustaining cost of ~$555 per ton. 5E intends to sell boric acid directly to industrial customers under long-term offtake agreements, with calcium chloride and gypsum as co-products. Longer term, 5E aims to move downstream into higher-margin advanced boron derivatives through R&D, partnerships, or acquisitions.