Inigneous

Inigneous is a fictional igneous rock type used in worldbuilding and educational contexts. It is defined as a crystallized rock formed by the cooling and solidification of molten material, with a distinctive internal crystalline network that can give a subtle glassy sheen on fresh exposure.

Etymology: The name blends the word igneous with a prefix intended to signal an internal or variant form, and it is not a term used in real-world geology. The designation is primarily used for teaching and speculative geology.

Formation and composition: Inigneous is typically described as forming from mafic magmas that crystallize rapidly near or at the crust, producing a porphyritic texture with larger phenocrysts embedded in a finer-grained or glassy groundmass. Common minerals are imagined to include plagioclase, pyroxene, and olivine, with minor accessory minerals such as magnetite and apatite. The texture can range from granular to visually mottled, with occasional vesicles in more eruptive variants.

Occurrence and use: Inigneous is portrayed as occurring on a fictional planetary body, for example the planet Inignea, in volcanic regions where shallow magmatic intrusion is prevalent. In practical worldbuilding, it is proposed as a decorative stone for sculpture or architecture, as well as a teaching example to illustrate cooling histories, crystallization sequences, and igneous textures without reference to actual rocks.