The term SEAM STUFF is a collective term for the materials found in COAL seams. ORE is a three-letter word that refers to a mineral or rock from which a valuable metal or other material can be extracted. COAL is a four-letter word that refers to a combustible black or dark brown sedimentary rock composed mainly of carbon and hydrocarbons. Together, these two words refer to the materials found in COAL seams, which are mined for their valuable resources.