minerals that have the same chemical formula but different crystal structures are _____.
Notice that graphite, commonly seen in pencil lead, and diamonds. have the same chemical formula. Minerals with the same chemical formula but. different crystal structures are called polymorphs. These minerals have different. types of chemical bonds and, thus, different crystal forms. If a substance fails any part of this definition, it is not a mineral. For example, table sugar, an organic compound formed by biological plant activity, fits all. facets of the definition except the inorganic part.