Mineral

Example:

Imagine trying to find the perfect piece to complete a jigsaw puzzle, where each piece has a unique shape, color, and pattern. This search is similar to how minerals are defined by their unique and specific characteristics, such as a definite chemical composition and crystal structure. Just as each puzzle piece fits only one specific place in the puzzle, each mineral is a distinct "piece" of the Earth's geological puzzle, defined by its precise chemical formula and orderly structure.