"Manufacturing" refines, improves, changes the condition of raw materials or converts the form of the materials into new, different or more useful property and includes the fabrication or production of special made-to-order articles and the generation of electricity. A person who is engaged in manufacturing and non-manufacturing activities may be classified as a manufacturer as to his manufacturing activities that are operated as a separate business or division.
35 Miss. Code. R. § 4-07-03-202