Final answer:
Minerals that can exhibit more than one crystalline structure despite having the same chemical composition are known as polymorphs. This occurrence, called polymorphism, can happen in any crystalline material. Carbon, for instance, can be found as diamond and graphite, which are allotropes of each other.
Step-by-step explanation:
A mineral of a given composition that can exhibit more than one crystalline structure is known as a polymorph. Polymorphism refers to a condition where a solid material exists in more than one form or crystal structure. This phenomenon can be observed in various crystalline materials, including minerals, polymers, and metals.
For example, the chemical formula for olivine is (Mg,Fe)2SiO4, which indicates that its magnesium and iron content can vary while still maintaining its distinct crystalline structures. Similarly, carbon can exist as both diamond and graphite, which are allotropes - two or more forms of the same element that, while in the same physical state, have different internal structures.
A mineral is a naturally occurring, inorganic, solid substance with a definite chemical composition. Its internal atomic arrangement gives rise to a characteristic crystalline structure, which might involve multiple geometric arrangements known as polymorphism.