Introduction: What Is a mineral a Mineral Naturally formed, inorganic, solid material with a specific chemical composition and a characteristic crystalline structure. Rock Naturally formed coherent mass of one or more minerals, sometimes including organic debris.◼ Mineral ◼ Naturally formed, inorganic, solid material with a specific chemical composition and a characteristic crystalline structure. ◼ Rock Naturally formed, coherent mass of one or more minerals, sometimes including organic debris. Introduction : What Is A Mineral?