The term REFINER'S SUPPLY is a crossword solution composed of three letters: ORE. ORE stands for a mineral or rock that contains valuable metals, such as gold, silver, and copper, which can be mined and extracted. Refiners use the ORE to extract the valuable metals, which are then used in various industries. Refiner's Supply is a company that specializes in providing refiners with the necessary supplies and equipment to extract the valuable metals from ORE.