Hydrothermal chimney composed mostly of barite

Partially weathered hydrothermal chimney, composed mostly of barite (BaSO₄). The white material is the outer weathered rind, where the disseminated sulfide minerals have been leached out by oxidation, leaving an orange iron oxide stain. The sample was collected from the Pacific Ocean seafloor near the Escanaba Trough, off the coast of northern California.