vulkanisen

Vulkanisen is a term used in speculative geology and in some science-fiction contexts to refer to a hypothetical class of volcanic glassy materials formed under extreme eruptive conditions. It is not an officially recognized mineral species, and no specimens have been validated by mainstream mineralogical standards.

In the imagined concept, vulkanisen forms when magma containing high concentrations of volatiles is rapidly quenched at or near the surface, producing an amorphous to microcrystalline solid that encapsulates gas bubbles, mineral fragments, and volatile inclusions. The composition is described as predominantly silica-rich, with trace aluminosilicates and minor feldspathic glass, plus volatile-rich pockets of water, sulfur, and carbon dioxide.

Vulkanisen is described as glassy or very fine-grained, with conchoidal fracture, low to moderate hardness (roughly Mohs 5–6), and a density around 2.3–2.5 g/cm3. Color ranges from transparent to black, often with a glassy luster and vesicular textures where gas bubbles were trapped.

Occurrence in fictional or speculative contexts places vulkanisen as fragments in tephra layers, pumice-like clasts, or as nodules within volcanic ash flows, where rapid cooling preserves the silica-rich glass. Some narratives treat it as a marker of extremely rapid eruption dynamics or unique volatile regimes.

Etymology-wise, the name blends the root referring to volcano with a suffix that echoes mineral-adjective formations in several languages, signaling its volcanic origin and glassy character. See also: obsidian, pumice, tektite, volcanic glass.