Ferroan

Part of speech: adjective

Definitions

1. A category of minerals identified by varying levels of iron that influence their physical and chemical properties
2. Relating to minerals that have an iron component, which can significantly modify their structural traits and classifications
3. A classification of certain minerals distinguished by the presence of iron, altering their chemical behaviors and structural characteristics

Etymology: "Ferroan" is a plain technical formation: "ferro-", a combining form from Latin "ferrum" meaning iron, joined to the adjectival suffix "-an". The suffix is the same one found in words like "Lutheran" or "Jovian," where it signals belonging to or relating to a particular thing. Put together, the term simply means "relating to iron" or "containing iron." In mineralogy, the word is used to sort members of a mineral group by how much iron they contain. Many minerals form continuous series in which iron can substitute for other metals in the crystal structure, so a mineral with a high iron content is described as ferroan, while one with little iron is called magnesian or otherwise named by its composition. The iron content shifts colour, density and other properties, which is why the distinction matters to geologists.