Final answer:
An organic substance is not required for a material to be considered a mineral; a mineral must be inorganic, naturally occurring, with a definite chemical composition and a crystalline structure.
Step-by-step explanation:
The substance that is not required for a substance to be considered a mineral is organic. A mineral is defined as a naturally occurring, inorganic solid with a definite chemical composition and a characteristic crystalline structure.
Minerals cannot be composed of the complex carbon molecules that characterize life forms, therefore, they must be inorganic. Furthermore, minerals are typically a combination of metals and nonmetals and have a crystal structure that is an outward manifestation of the internal atomic arrangement. An example of a mineral's chemical composition is halite with a formula of NaCl, demonstrating that minerals have specific chemical make-ups.