Final answer:
In terms of mineral formation, 'naturally occurring' refers to minerals formed by natural geological processes without human input. These minerals are inorganic, solid substances with a definite chemical composition and a distinctive crystalline structure, serving as the essential building blocks of rocks and soils.
Step-by-step explanation:
A mineral is defined as a naturally occurring, inorganic solid with a definite chemical composition and a characteristic crystalline structure. The term naturally occurring indicates that the mineral was formed through natural geological processes without human intervention. Minerals are inorganic, meaning they do not contain complex carbon molecules that signify life, and they exist in a solid state at room temperature. For example, while water is not considered a mineral due to its liquid state, ice does qualify as a mineral when it forms naturally and is not man-made.
To have a definite chemical composition, a mineral needs a specific chemical formula such as sodium chloride (NaCl) for halite. Some minerals, like olivine with the formula (Mg,Fe)2SiO4, can have a range of compositions due to the substitution of similar elements. The atoms in minerals are arranged in an orderly pattern, giving rise to the mineral's crystalline structure, which is visible through characteristics like symmetry and facets.
Minerals are critical as they are the primary building blocks of rocks. A rock such as granite is composed of a combination of different minerals. The formation of soils is also a testament to the enduring, natural process of mineral and rock breakdown and transformation through natural and environmental forces.