Poreenite

Poreenite is a fictional mineral species commonly used in geology education and in speculative fiction to illustrate principles of mineral classification and petrology. The name is derived from the fictional Poreen Range in the hypothetical geologic model introduced by geologist Lina Thorne in 2010.

It is described as a green to olive-colored silicate mineral with a vitreous to resinous luster. It typically occurs as prismatic crystals and granular aggregates. Hardness on Mohs scale is given as 5.5–6.0; specific gravity around 3.2–3.6. It is said to crystallize in the monoclinic or orthorhombic system in many depictions, with one good cleavage direction. The mineral is described as environmentally responsive to alteration, forming secondary clinohumite-like minerals under ultramafic metamorphism.

Its general composition is given as (Fe2+,Mg)2Al4Si6O20(OH)4 with variable Fe/Mg substitution and traces of Cr or Ti that color the crystals. In common simulations, it forms through metasomatic replacement of aluminosilicate precursors in subduction-zone analog models.

In fictional models, Poreenite forms in high-pressure, low-temperature metamorphic belts adjacent to ultramafic rocks, with associated minerals such as serpentine, chlorite, and calcite.

Used in teaching to illustrate solid-solution series, mineral classification, and the concept of fictional trace elements. Not recognized as a real mineral in scientific databases.